Lancet Device

ABSTRACT

The lancet device includes a housing and a lancet having a puncturing element. The lancet is disposed within the housing and is adapted for axial movement between an initial or pre-actuated position wherein the puncturing element is retained within the housing, and a puncturing position wherein the puncturing element extends through a forward opening in the housing. The lancet device includes a drive spring disposed within the housing for biasing the lancet toward the puncturing position, and a retraction or return spring for returning the lancet to a position within the housing where the puncturing element is disposed within the housing. The retraction spring thereafter maintains engagement with the lancet to assist in preventing the puncturing element from again projecting outward from the forward opening in the housing.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a divisional of U.S. patent application Ser.No. 14/543,168, filed Nov. 17, 2014 entitled “Lancet Device”, which is acontinuation of U.S. patent application Ser. No. 13/669,792, filed Nov.6, 2012, now U.S. Pat. No. 8,998,942, entitled “Lancet Device”, which isa divisional application of U.S. patent application Ser. No. 11/910,629,filed Oct. 6, 2008, now U.S. Pat. No. 8,333,781, which is a nationalstage application under 35 U.S.C. § 371 of International ApplicationPCT/US06/13470 filed Apr. 7, 2006, the entire disclosures of each ofwhich are hereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates generally to medical puncturing devices, commonlyreferred to as lancets, which are used to take blood samples frompatients and, more specifically, to a lancet device that is designed forease of use with activation achieved during contact of the device innormal use.

Description of Related Art

Lancet devices are used in the medical field for puncturing the skin ofa patient to obtain a capillary blood sample from the patient. Certaindiseases, such as diabetes, require that the patient's blood be testedon a regular basis to monitor, for example, the patient's blood sugarlevels. Additionally, test kits, such as cholesterol test kits, oftenrequire a blood sample for analysis. The blood collection procedureusually involves pricking a finger or other suitable body part in orderto obtain the blood sample. Typically, the amount of blood needed forsuch tests is relatively small and a small puncture wound or incisionnormally provides a sufficient amount of blood for these tests.

Various lancet devices are commercially available to hospitals, clinics,doctors' offices, and the like, as well as to individual consumers. Suchdevices typically include a sharp-pointed member such as a needle, or asharp-edged member such as a blade, that is used to make a quickpuncture wound or incision in the patient's skin in order to provide asmall outflow of blood. It is often physiologically and psychologicallydifficult for many people to prick their own finger with a hand-heldneedle or blade. As a result, lancet devices have evolved into devicesthat facilitate puncturing or cutting the skin of the patient upon theactuation of a triggering mechanism. In some devices, the needle orblade is kept in a standby position until it is triggered by the user,who may be a medical professional in charge of drawing blood from thepatient, or the patient himself or herself. Upon triggering, the needleor blade punctures or cuts the skin of the patient, for example on thefinger. Often, a spring is incorporated into the device to provide the“automatic” force necessary to puncture or cut the skin of the patient.

It is of the utmost importance in the medical field that such medicalpuncturing devices or lancets are in a sterile condition before use.Today, generally without exception, medical puncturing devices orlancets are manufactured and packaged in a sterilized condition beforethey are distributed to medical professionals and members of the publicwho have a need for such devices. The sterile packaging maintains thesterility of the device, ensuring that the surrounding environment doesnot contaminate it until use. In addition, it is also of increasingimportance that the user or another person does not come into contactwith the needle or blade after use of the device. With the concern overblood-borne diseases, medical professionals are required to take greatcare with medical devices that come into contact with the blood ofpatients. Thus, an important aspect of lancet design involves preventingthe needle or blade of the device from wounding the user or anotherperson after the blood sample is drawn from the patient. Once used, theneedle or blade should be shielded to prevent the needle or blade fromwounding the user or another person handling the device. Moreover, thelancet device should be disposable to eliminate the chances of diseasetransmission due to the needle or blade being used on more than oneperson. In this regard, the lancet device should ideally be designed forone firing, and have safety features to prevent reuse.

Advances have been made in recent years to increase safety in operatingand handling used lancet devices. For example, lancet devices arecurrently available which are single shot devices that feature automaticejection and retraction of the puncturing or cutting element from andinto the device. Examples of such medical puncturing devices aredisclosed in U.S. Pat. Nos. 6,432,120; 6,248,120; 5,755,733; and5,540,709.

U.S. Pat. No. 6,432,120 to Teo discloses a lancet device that includes alancet holder which contains a spring-loaded lancet structure. Thespring-loaded lancet structure includes a single spring that effects theejection and retraction of a lancet needle upon the triggering of thestructure. U.S. Pat. No. 6,248,120 to Wyszogrodzki discloses a lancetdevice comprised of a housing, a shielding portion, a piston with apuncturing tip, and drive and return springs that eject and retract thepiston, respectively, upon the breakage of internal wing elements in thehousing. U.S. Pat. No. 5,755,733 to Morita discloses a lancet devicethat includes a combined holder and lancet structure. The lancetstructure includes a lancet member with a puncturing tip and acompressible spring member that causes the lancet member to puncture theskin of a patient upon actuation of a pair of actuating arms.

U.S. Pat. No. 5,540,709 to Ramel discloses a lancet device that includesa housing enclosing a slidable trigger, which is used to trigger acompressed spring that powers a piercing lancet member to pierce theskin of a patient. The housing includes a pair of internal fingers thatengage the body of the lancet member, which are then released ofengagement with the lancet member body by axial force applied by theuser to the slidable trigger. Other medical puncturing devices orlancets known in the art are disclosed in U.S. Pat. Nos. 4,869,249 and4,817,603. The devices disclosed in these references include a cap thatis used to protect a needle or to keep the needle sterile.

In view of the foregoing, a need generally exists in the medical fieldfor a medical puncturing device that is easy for a user to manipulateand use while ensuring sterility before use and safe and secure disposalafter use. Additionally, a need exists in the medical field for asimple, inexpensive, reliable, and disposable medical puncturing devicefor use in collecting blood samples.

SUMMARY OF THE INVENTION

The present invention is generally directed to a lancet device. Thelancet device according to a first embodiment comprises a housing, ashield at least partially disposed within the housing and movablyassociated therewith, and a lancet disposed in the housing and axiallymovable through the shield. The lancet comprises a puncturing element,and is adapted for axial movement between an initial position whereinthe puncturing element is disposed within the housing and a puncturingposition wherein the puncturing element extends through a forwardopening in the shield for a puncturing procedure. A drive spring isdisposed between a rearward end of the housing and the lancet forbiasing the lancet to the puncturing position. The lancet device furthercomprises an actuator associated with the shield and in interferenceengagement with the lancet in the initial position. In operation, axialmovement of the shield into the housing causes the actuator to move thelancet toward and contact the rearward end of the housing to at leastpartially compress the drive spring. Upon contact with the rearward endof the housing, further force applied to retract the shield into thehousing causes failure of the interference engagement between theactuator and the lancet thereby releasing the at least partiallycompressed drive spring and permitting the drive spring to bias thelancet through the shield to the puncturing position. The actuatorcomprises a shearable element associated with a proximal end of theshield, and the shearable element may comprise at least one breakableshelf or tab providing the interference engagement with the lancet.

The lancet device according to a second embodiment comprises a housing,a shield at least partially disposed within the housing and movablyassociated therewith, with the shield comprising at least one internaltab, and a lancet disposed in the housing and axially movable throughthe shield. The lancet comprises a puncturing element, and is adaptedfor axial movement between an initial position wherein the puncturingelement is disposed within the housing and a puncturing position whereinthe puncturing element extends through a forward opening in the shieldfor a puncturing procedure. The lancet is in interference engagementwith the internal tab in the shield in the initial position. A drivespring is disposed between a rearward end of the housing and the lancetfor biasing the lancet to the puncturing position. In operation, axialmovement of the shield into the housing causes the lancet to move towardand contact the rearward end of the housing due to the interferenceengagement with the shield internal tab to at least partially compressthe drive spring. Upon contact with the rearward end of the housing,further force or movement applied to retract the shield into the housingcauses failure of the internal tab removing the interference engagementand releasing the at least partially compressed drive spring to bias thelancet through the shield to the puncturing position. The lancet maycomprise a cutting element providing the interference engagement withthe internal tab in the initial position of the lancet, and failure ofthe internal tab may be caused by the cutting element cutting throughthe internal tab.

The lancet device according to a third embodiment comprises a housing, ashield at least partially disposed within the housing and movablyassociated therewith, and a lancet disposed in the housing and axiallymovable through the shield and comprising a puncturing element. Thelancet is generally adapted for axial movement between an initialposition wherein the puncturing element is disposed within the housingand a puncturing position wherein the puncturing element extends througha forward opening in the shield for a puncturing procedure. A drivespring is disposed between a rearward end of the housing and the lancetfor biasing the lancet to the puncturing position. The lancet devicefurther comprises an actuator in interference engagement with the lancetin the initial position and maintains the drive spring in an at leastpartially compressed state in the initial position of the lancet. Theactuator comprises a sleeve portion associated with the housing and atleast one elastic element in interference engagement with the lancet. Inoperation, axial movement of the shield into the housing causes theshield to move the elastic element radially outward from the lancetreleasing the interference engagement therewith, and thereby releasingthe at least partially compressed drive spring to bias the lancetthrough the shield to the puncturing position. The sleeve portion andelastic element may be formed integrally and connected, for example, bya living hinge.

The lancet device according to fourth embodiment comprises a housing anda lancet disposed in the housing and axially movable through the housingand comprising a puncturing element. The lancet is adapted for axialmovement between an initial position wherein the puncturing element isdisposed within the housing and a puncturing position wherein thepuncturing element extends through a front opening in the housing for apuncturing procedure. A drive spring is disposed between a rearward endof the housing and the lancet for biasing the lancet to the puncturingposition. The drive spring is held in at least partially compressedstate between the rearward end of the housing and the lancet by aninterference engagement between the lancet and housing. The lancetdevice further comprises an actuator pivotally connected to the housingand in contact engagement with the lancet in the initial position forcausing release of the drive spring. In operation, movement, typicallydepression, of the actuator causes pivotal movement thereof into thehousing causing at least a portion of the lancet to move downward in thehousing until the lancet is released of interference engagement with thehousing, thereby releasing the at least partially compressed drivespring to bias the lancet through the housing to the puncturingposition. The lancet may comprises at least one outward-extending guidetab and the housing may define an internal guide channel comprising alongitudinal main channel and a generally transverse side channel, suchthat the interference engagement comprises the guide tab engaging acorner or vertex defined generally at the intersection of the mainchannel and side channel.

The lancet device according to a fifth embodiment comprises a housinghaving an internal cam surface at a rearward end thereof, a shield atleast partially disposed within the housing and movably associatedtherewith, and a lancet disposed in the housing and axially movablethrough the shield and comprising a puncturing element. The lancet isadapted for axial movement between an initial position wherein thepuncturing element is disposed within the housing and a puncturingposition wherein the puncturing element extends through a forwardopening in the shield for a puncturing procedure. A drive spring isdisposed between the rearward end of the housing and the lancet forbiasing the lancet to the puncturing position. The lancet device furthercomprises an actuator associated with a proximal end of the shielddisposed in the housing and in interference engagement with the lancetin the initial position thereof. In operation, axial movement of theshield into the housing causes the actuator to move the lancet towardthe rearward end of the housing to at least partially compress the drivespring while simultaneously interacting with the internal cam surface.Continued interaction with the internal cam surface during the shieldaxial movement further moves the actuator to a position within thehousing where the interference engagement between the actuator and thelancet is released, thereby releasing the at least partially compresseddrive spring and permitting the drive spring to bias the lancet throughthe shield to the puncturing position. The actuator may comprise a platemember slidably associated with the shield proximal end and defining akeyhole for permitting passage of the lancet therethrough to release theinterference engagement.

The lancet device according to a sixth embodiment comprises a housingand a lancet disposed in the housing and axially movable through thehousing. The lancet device comprises a puncturing element, and isadapted for axial movement between an initial position wherein thepuncturing element is disposed within the housing and a puncturingposition wherein the puncturing element extends through a front openingin the housing for a puncturing procedure. A drive spring is disposedbetween a rearward end of the housing and the lancet for biasing thelancet to the puncturing position. The lancet device further comprisesan actuator associated with the housing and in interference engagementwith the lancet in the initial position. The interference engagementbetween actuator and lancet maintains the drive spring in at least apartially compressed state between the rearward end of the housing andthe lancet in the initial position. In operation, movement, typicallydepression, of the actuator into the housing moves the actuator to aposition within the housing where the interference engagement betweenthe actuator and the lancet is released, thereby releasing the at leastpartially compressed drive spring and permitting the drive spring tobias the lancet through the shield to the puncturing position. Theactuator may comprise a lever member pivotally connected to the housingand a plate member depending into the housing. The plate member definesa keyhole for permitting passage of the lancet therethrough to releasethe interference engagement. The lancet device, according to a seventhembodiment, may include the actuator comprising a depressible buttonassociated with the housing and a plate member depending into thehousing, with the plate member defining a keyhole for permitting passageof the lancet therethrough to release the interference engagement.

The lancet device according to an eighth embodiment comprises a housing,a lancet disposed in the housing and axially movable through the housingand comprising a puncturing element. The lancet is adapted for axialmovement between an initial position wherein the puncturing element isdisposed within the housing and a puncturing position wherein thepuncturing element extends through a front opening in the housing for apuncturing procedure. A drive spring is disposed between a rearward endof the housing and the lancet for biasing the lancet to the puncturingposition. The drive spring is held in at least a partially compressedstate between the rearward end of the housing and the lancet by aninterference engagement between the lancet and housing. The lancetdevice further comprises an actuator connected or optionally integratedpivotally to the housing and adapted to sever the interferenceengagement between the lancet and housing for causing release of thedrive spring. In operation, movement, typically depression, of theactuator causes pivotal movement thereof into the housing until theactuator severs the interference engagement between the lancet andhousing thereby releasing the at least partially compressed drive springto bias the lancet through the housing to the puncturing position. Theactuator may comprise a lever member connected pivotally to the housingand comprising a depending cutting edge for severing the interferenceengagement between the lancet and housing.

The lancet device according to a further embodiment comprises a housingand a lancet disposed within the housing and comprising a puncturingelement. The lancet is adapted for axial movement between an initial,pre-actuated position wherein the puncturing element is retained withinthe housing and a puncturing position wherein the puncturing elementextends through a front opening the housing. A drive spring is disposedbetween a rearward end of the housing and the lancet for biasing thelancet toward the puncturing position. The lancet device furthercomprises a retaining hub retaining the lancet in the pre-actuatedposition. The retaining hub is adapted to retain the lancet against thebias of the drive spring, and comprises a pivotal cam element. The camelement is in interference engagement with the lancet in thepre-actuated position of the lancet. In operation, axial movement of thehousing toward the retaining hub causes the cam element to pivot,thereby moving the lancet toward the rearward end of the housing to atleast partially compress the drive spring and releasing the cam elementfrom interference engagement with the lancet, permitting the drivespring to drive the lancet through the housing toward the puncturingposition. The cam element may define a recess or notch which releasesthe cam element from the interference engagement with the lancet whenthe cam element is pivoted to align the recess with an interfering onthe lancet.

The lancet device may further comprise an internal contact within thehousing and axial movement of the housing toward the retaining hubcauses the internal contact within the housing to pivot the cam element.The cam element may comprise a contact surface for engagement with theinternal contact of the housing. The internal contact of the housing maycomprise an integrally formed cam surface for cooperating engagementwith the contact surface of the cam element. The retaining hub maycomprise an annular rim, generally defined by a pair of opposed supportmembers connected by a pair of pivotal cam elements. The cam elementsmay comprise pivotal shafts connecting the support members.

The lancet device according to a final embodiment generally comprises ahousing including an internal actuation member, a shield at leastpartially disposed within the housing and movably associated therewith,a lancet disposed in the housing and axially movable through the shield,and a rotation element. The lancet includes a puncturing element and isadapted for axial movement between an initial position wherein thepuncturing element is disposed within the housing, and a puncturingposition wherein the puncturing element extends through a forwardopening in the shield for a puncturing procedure. A drive spring istypically disposed between a rearward end of the housing and the lancetfor biasing the lancet to the puncturing position. The lancet istypically in interference engagement with the rotation element in theinitial position. In operation, axial movement of the shield into thehousing causes the actuation member to rotate the rotation elementrelative to the lancet to a release position releasing the interferenceengagement between the lancet and rotation element, thereby permittingthe drive spring to bias the lancet through the shield to the puncturingposition.

The rotation element may be associated with the shield such that axialmovement of the shield into the housing causes the drive spring to atleast partially compress between the housing rearward end and lancet dueto the interference engagement between the lancet and rotation element.The rotation element may be associated with a rearward end of the shielddisposed in the housing.

The actuating member may comprise a cam element with a cam surface andthe rotation element may comprise a guide plate defining a cam guiderecess for receiving the cam element, such that axial movement of theshield into the housing causes the cam surface to engage the cam guiderecess an impart rotational motion to the guide plate. The lancet maycomprise an actuation tab in interference engagement with the guideplate, and the guide plate may define a clearance slot, such that theinterference engagement may be released when the guide plate rotates tothe release position where the actuation tab aligns with the clearanceslot.

The actuating member may comprise a cam element with a cam surface andthe rotation element may comprise a cam follower, such that axialmovement of the shield into the housing causes the cam surface to engagethe cam follower an impart rotational motion thereto at least until thecam follower reaches the release position.

Further details and advantages of the invention will become clear fromthe following detailed description when read in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal cross-sectional view of a first embodiment of alancet device showing the lancet device in an initial, pre-actuatedstate;

FIG. 2 is a longitudinal cross-sectional view of the lancet device ofFIG. 1 taken along a perpendicular longitudinal axis to thecross-sectional view in FIG. 1;

FIG. 3 is a longitudinal cross-sectional view of the lancet device ofFIG. 1 showing the lancet device in an initial stage of actuation;

FIG. 4 is a longitudinal cross-sectional view of the lancet device ofFIG. 1 showing the lancet device immediately after actuation;

FIG. 5 is a longitudinal cross-sectional view of the lancet device ofFIG. 1 showing the lancet device after actuation with a lancet of devicepartially exposed for a puncturing procedure;

FIG. 6 is a longitudinal cross-sectional view of the lancet device ofFIG. 1 showing the lancet device in a final state after actuation;

FIG. 7 is a longitudinal cross-sectional view of a second embodiment ofthe lancet device showing the lancet device in the initial, pre-actuatedstate;

FIG. 8 is a longitudinal cross-sectional view of the lancet device ofFIG. 7 taken along a perpendicular longitudinal axis to thecross-sectional view in FIG. 7;

FIG. 9 is a longitudinal cross-sectional view of the lancet device ofFIG. 7 showing the lancet device in the initial stage of actuation;

FIG. 10 is a longitudinal cross-sectional view of the lancet device ofFIG. 7 with the lancet of device removed for viewing the interior of thedevice;

FIG. 11 is a longitudinal cross-sectional view of the lancet device ofFIG. 7 showing the lancet device after actuation with the lancet ofdevice partially exposed for a puncturing procedure;

FIG. 12 is a longitudinal cross-sectional view of the lancet device ofFIG. 7 showing the lancet device in the final state after actuation;

FIG. 13 is a longitudinal cross-sectional view of a third embodiment ofthe lancet device showing the lancet device in the initial, pre-actuatedstate;

FIG. 14 is a longitudinal cross-sectional view of the lancet device ofFIG. 13 showing the lancet device in the initial stage of actuation;

FIG. 15 is a longitudinal cross-sectional view of the lancet device ofFIG. 13 showing the lancet device in a later stage of actuation;

FIG. 16 is a cross-sectional view of the lancet device of FIG. 13showing the lancet device immediately after actuation;

FIG. 17 is a longitudinal cross-sectional view of the lancet device ofFIG. 13 showing the lancet device after actuation with the lancet of thedevice partially exposed for a puncturing procedure;

FIG. 18 is a longitudinal cross-sectional view of the lancet device ofFIG. 13 showing the lancet device in the final state after actuation;

FIG. 19 is a longitudinal cross-sectional view of a fourth embodiment ofthe lancet device showing the lancet device in the initial, pre-actuatedstate;

FIG. 20 is a longitudinal cross-sectional view of the lancet device ofFIG. 19 showing the lancet device in the initial stage of actuation;

FIG. 21 is a cross-sectional view of the lancet device of FIG. 19showing the lancet device immediately after actuation;

FIG. 22 is a longitudinal cross-sectional view of the lancet device ofFIG. 19 with the lancet of the device removed for viewing the interiorof the device;

FIG. 23 is a longitudinal cross-sectional view of the lancet device ofFIG. 19 showing the lancet device after actuation with the lancet of thedevice partially exposed for a puncturing procedure;

FIG. 24 is a longitudinal cross-sectional view of a fifth embodiment ofthe lancet device showing the lancet device in the initial, pre-actuatedstate;

FIG. 25 is longitudinal cross-sectional view of the lancet device ofFIG. 24 taken along a perpendicular longitudinal axis to thecross-sectional view in FIG. 24;

FIG. 26 is a transverse cross-sectional view of the lancet device ofFIG. 24 showing the lancet device in the initial stage of actuation withthe lancet in an interference engagement within the device;

FIG. 27 is a transverse cross-sectional view of the lancet device ofFIG. 24 showing the lancet device at the point of actuation with thelancet released of the interference engagement within the device;

FIG. 28 is a longitudinal cross-sectional view of the lancet device ofFIG. 24 showing the lancet device in the initial stage of actuation

FIG. 29 is a longitudinal cross-sectional view of the lancet device ofFIG. 24 showing the lancet device at the point of actuation;

FIG. 30 is a longitudinal cross-sectional view of the lancet device ofFIG. 24 showing the lancet device after actuation with the lancet of thedevice partially exposed for a puncturing procedure;

FIG. 31 is a longitudinal cross-sectional view of a sixth embodiment ofthe lancet device showing the lancet device in the initial, pre-actuatedstate;

FIG. 32 is a second longitudinal cross-sectional view of the lancetdevice of FIG. 31 showing the lancet device in the initial, pre-actuatedstate;

FIG. 33 is a transverse cross-sectional view of the lancet device ofFIG. 31 showing the lancet device in the initial stage of actuation withthe lancet in an interference engagement within the device;

FIG. 34 is a transverse cross-sectional view of the lancet device ofFIG. 31 showing the lancet device at the point of actuation with thelancet released of the interference engagement within the device;

FIG. 35 is a longitudinal cross-sectional view of the lancet device ofFIG. 31 showing the lancet device in the initial stage of actuation;

FIG. 36 is a longitudinal cross-sectional view of the lancet device ofFIG. 31 showing the lancet device at the point of actuation;

FIG. 37 is a longitudinal cross-sectional view of the lancet device ofFIG. 31 showing the lancet device after actuation with the lancet movingwithin the device toward a puncturing position;

FIG. 38 is a longitudinal cross-sectional view of a seventh embodimentof the lancet device showing the lancet device in the initial,pre-actuated state;

FIG. 39 is a longitudinal cross-sectional view of the lancet device ofFIG. 38 showing the lancet device in the initial stage of actuation withthe lancet in an interference engagement within the device;

FIG. 40 is a transverse cross-sectional view of the lancet device ofFIG. 38 showing the lancet device at the point of actuation with thelancet released of the interference engagement within the device;

FIG. 41 is a longitudinal cross-sectional view of the lancet device ofFIG. 38 showing the lancet device after actuation with the lancet movingwithin the device toward a puncturing position;

FIG. 42 is a longitudinal cross-sectional view of the lancet device ofFIG. 38 showing the lancet device after actuation with the lancet ofdevice in the puncturing position for a puncturing procedure;

FIG. 43 is a longitudinal cross-sectional view of the lancet device ofFIG. 38 showing the lancet device in the final state after actuation;

FIG. 44 is a perspective view of an eighth embodiment of the lancetdevice;

FIG. 45 is a perspective view of the lancet device of FIG. 44 with asterile cover associated with the internal lancet removed;

FIG. 46 is an exploded perspective view of the lancet device of FIG. 44;

FIG. 47 is a perspective view of a portion of the lancet device of FIG.44 showing an actuator, a drive spring, and the lancet of the device;

FIG. 48 is a longitudinal cross-sectional view of the lancet device ofFIG. 44 showing the lancet device in the initial, pre-actuated state;

FIG. 49 is a longitudinal cross-sectional view of the lancet device ofFIG. 44 taken along a perpendicular longitudinal axis to thecross-sectional view in FIG. 48;

FIG. 50 is a longitudinal cross-sectional view of the lancet device ofFIG. 44 showing the lancet device at the point of actuation;

FIG. 51 is a longitudinal cross-sectional view of the lancet device ofFIG. 44 showing the lancet device after actuation with the lancet of thedevice partially exposed for a puncturing procedure;

FIG. 52 is a longitudinal cross-sectional view of the lancet device ofFIG. 44 showing the lancet device in the final state after actuation;

FIG. 53 is a perspective view of a further embodiment of the lancetdevice;

FIGS. 54A-54C are bottom, side, and end views, respectively, of aretaining hub used in the lancet device shown in FIG. 53;

FIG. 55 is a perspective view of the retaining hub shown in FIGS.54A-54C

FIG. 56 is a perspective view of a final embodiment of the lancetdevice;

FIG. 57 is a longitudinal cross-sectional view of the lancet device ofFIG. 56;

FIG. 58 is a transverse cross-sectional view of the lancet device ofFIG. 56 taken along line 58-58 in FIG. 57;

FIG. 59 is an exploded and partial cross-sectional view of the lancetdevice of FIG. 56 showing a rear cap, guide plate and shield of thelancet device;

FIG. 60 is a perspective view of a lancet used in the lancet device ofFIG. 56;

FIG. 61 is a perspective view of a rearward portion of the lancet ofFIG. 60 showing the lancet associated with the shield and guide plateshown in FIG. 59;

FIG. 62 is a side view of the assembled structure shown in FIG. 61additionally including the rear cap shown in FIG. 59;

FIG. 63 is a perspective view of a rearward end of a shield with alancet movable through the shield in accordance with the lancet deviceof FIG. 56;

FIG. 64 is a perspective view of a forward end of the shield of thelancet device of FIG. 56;

FIGS. 65A and 65B are longitudinal and transverse cross-sectional views,respectively, of the lancet device of FIG. 56 showing the lancet devicein an initial, pre-actuated state;

FIGS. 66A and 66B are longitudinal and transverse cross-sectional views,respectively, of the lancet device of FIG. 56 showing the lancet devicein an initial stage of actuation; and

FIGS. 67A and 67B are longitudinal and transverse cross-sectional views,respectively, of the lancet device of FIG. 56 showing the lancet deviceat the point of actuation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For purposes of the description hereinafter, spatial orientation terms,if used, shall relate to the embodiment of the invention as it isoriented in the accompanying drawing figures. However, it is to beunderstood that the invention may assume many alternative variations andembodiments except where expressly specified to the contrary. It is alsoto be understood that the specific devices and embodiments illustratedin the accompanying drawing figures and described herein are simplyexemplary embodiments of the invention, and wherein like elements aredesignated with like reference numerals and an accompanying alphabeticdesignation.

Referring to FIGS. 1-6, a lancet device 10 a according to a firstembodiment is generally shown. The lancet device 10 a generally includesa housing 12 a, a shield 14 a movably associated with the housing 12 a,and a lancet 70 a movably disposed in the housing 12 a. As described ingreater detail herein, shield 14 a is movably associated with thehousing 12 a, and is at least partially disposed within housing 12 a.The shield 14 a typically extends partially outward from the housing 12a, while the lancet 70 a is contained within housing 12 a and is axiallymovable through the shield 14 a.

The housing 12 a is generally in the form of an elongated body, referredto hereinafter as main body 20 a. The main body 20 a has a generallycylindrical and hollow configuration. The main body 20 a has a distal orforward end portion 22 a, and a rear cap 24 a forming a proximal orrearward end portion 26 a of the main body 20 a. The interior of mainbody 20 a is generally open and comprises an internal cavity or bore 28a. The internal cavity 28 a is closed at the rearward end due to thepresence of rear cap 24 a, and includes a front opening 30 a defined bya forward end portion 22 a of main body 20 a, and through which shield14 a extends. Main body 20 a and rear cap 24 a may be integrally formed.Alternatively, main body 20 a and rear cap 24 a may be separate elementsthat are affixed together to form housing 12 a, which facilitatesassembly of lancet device 10 a. As examples, main body 20 a and rear cap24 a may be affixed together through an appropriate medical gradeadhesive, or connected using inter-engaging structures providing amechanical engagement therebetween, such as a friction-fit or a snap-fitconnection. For example, main body 20 a may include an annular rim 32 adefining an annular groove 34 a, and rear cap 24 a may include a matingannular rim 36 a having a mating annular lip 38 a as mating elements.When main body 20 a and rear cap 24 a are connected, annular lip 38 aextends within the rear open end of main body 20 a, with annular lip 38a snap-fitting over annular rim 32 a and into annular groove 34 a ofmain body 20. It should be understood that the arrangement of suchelements is merely exemplary and may be reversed, and it is contemplatedthat other inter-fitting mechanical engagement arrangements may be usedto connect the main body 20 a and rear cap 24 a. Main body 20 a furthercomprises an internal ridge 40 a, typically a perimetrically-extendingridge 40 a forward of annular groove 34 a, the purpose and function ofwhich will be described herein. Further, main body 20 a of housing 12 amay include a forward rim 42 a formed as part of forward end portion 22a and which defines front opening 30 a.

As noted previously, shield 14 a extends outward at least partially fromfront opening 30 a in the forward end portion 22 a of main body 20 a.Shield 14 a is a generally cylindrical, hollow structure comprising ashield body 50 a having a distal or forward end 52 a and a proximal orrearward end 54 a, and defines an internal cavity or bore 56 a extendingtherethrough. The forward end 52 a of shield body 50 a defines a partialforward end wall 58 a defining a forward opening 60 a, through which apuncturing element of lancet 70 a extends when lancet device 10 a isactuated by a user as will be discussed in more detail herein. Theforward end wall 58 a generally defines a small contact area aboutforward opening 60 a for contacting an intended puncture area on apatient's body. The reduced contact area may be made smaller (i.e.,reduced in surface area) by providing a plurality of peripheralindentations (not shown) formed perimetrically in shield 14 a. Theexternal surface features of housing 12 a and shield 14 a may be formedin accordance with the ergonomic features and structure disclosed inco-pending application Ser. No. 11/123,849, filed Nov. 30, 2004,entitled “Lancet Device”, and naming Bradley Wilkinson as inventor. Thedisclosure of the foregoing “Lancet Device” application is incorporatedherein by reference thereto.

The shield 14 a is axially and slidably movable within housing 12 a. Theshield 14 a and housing 12 a may be coaxially associated, with theshield 14 a and housing 12 a coaxially disposed around a common CentralAxis A. The shield 14 a and housing 12 a may each be generallycylindrically shaped. A shearable element 62 a is further associatedwith shield 14 a. In particular, shearable element 62 a is disposed atthe rearward end 54 a of shield body 50 a and engages a rear rim 63 a ofshield body 50 a. Shearable element 62 a comprises an annular sleeveportion 64 a that extends axially in a distal direction along the outersurface of shield body 50 a. The annular sleeve 64 a receives therearward end 54 a of shield body 50 a so as to be positioned betweenshield body 50 a and main body 20 a of housing 12 a. In particular, theinner surface of annular sleeve 64 a engages a proximally-extendingportion of the outer surface of shield body 50 a at the rearward end 54a of shield body 50 a, while the outer surface of shearable element 62 aslidably cooperates with the inner surface of main body 20 a of housing12 a. Shearable element 62 a further typically comprises two opposingand inward-projecting breakable shelves or wings 66 a that engage lancet70 a as described further herein. While shearable element 62 a is shownwith two opposing and inward-extending shelves or wings 66 a, it will beappreciated that only one shelf or wing 66 a is necessary forinterference engagement with the lancet 70 a as described herein.Breakable shelves or wings 66 a may comprise a weakened area or scoreline 67 a for allowing the shelves 66 a to break (i.e., fail) whensufficient downward pressure is applied thereto as discussed herein.Breakable shelves or wings 66 a are generally inwardlyradially-extending cantilevers which may be made of a similar ordissimilar material compared to that chosen for shield 14 a.

Shearable element 62 a is adapted to slide in combination with shieldbody 50 a in main body 20 a of housing 12 a when axial motion isimparted to shield body 50 a, for example by axially retracting (i.e.,inserting) shield body 50 a into main body 20 a to actuate the lancetdevice 10 a as described herein. For this purpose and to properly engagethe rear rim 63 a on the rearward end 54 a of shield body 50 a,shearable element 62 a comprises an abutment recess 68 a defined bysleeve portion 64 a which engages the proximal or rearward end 54 a ofshield body 50 a, and rear rim 63 a in particular. Accordingly, anyaxial motion applied to shield body 50 a to retract (i.e., insert)shield body 50 a into main body 20 a of housing 12 a will be transmittedto shearable element 62 a through the interference engagement of rearrim 63 a in abutment recess 68 a. As a result, shearable element 62 awill slide within main body 20 a of housing 12 a along with shield body50 a when axial motion applied thereto for actuating the lancet device10 a. The captured portion of shield body 50 a may be secured in sleeveportion 64 a of shearable element 62 a so that there is tight engagementbetween these elements and ensuring that axial motion imparted to shieldbody 50 a will be transmitted to shearable element 62 a. For example, amedical grade adhesive or mechanical locking engagement may be providedbetween the inner surface of sleeve portion 64 a and the capturedportion (i.e., outer surface) of shield body 50 a at the rearward end 54a of shield body 50 a to ensure that these elements are secured togetherand move as a unit in main body 20 a of housing 12 a. Forward rim 42 aof main body 20 a of housing 12 a is formed to provide an interferenceengagement with the distal end of sleeve portion 64 a of shearableelement 62 a to prevent shearable element 62 a and, consequently, shieldbody 50 a from axially sliding completely out of housing 12 a throughfront opening 30 a.

Lancet device 10 a further comprises a lancet 70 a disposed within thehousing 12 a, and extending into shield 14 a. Lancet 70 a includes apuncturing element shown in the form of a lancet 72 a. Lancet 72 acomprises a puncturing end 74 a at the forward end thereof. Lancet 70 ais adapted for axial movement through the internal cavity 56 a of shieldbody 50 a between an initial position, wherein the puncturing end 74 ais disposed within shield body 50 a to a puncturing position wherein thepuncturing end 74 a extends beyond the forward opening 60 a of shieldbody 50 a a sufficient distance to cause a puncture wound in a patient'sbody. Further details regarding the operation of lancet device 10 a andlancet 70 a are provided hereinafter.

The puncturing end 74 a of lancet 72 a is adapted for puncturing theskin of a patient, and may be in the form of a pointed end, needle tip,blade edge, and the like. Puncturing end 74 a may include a preferredalignment orientation, such as with a pointed end or a blade aligned ina specific orientation. In such an orientation, shield body 50 a and/ormain body 20 a of housing 12 a may include target indicia correspondingto the alignment orientation of puncturing end 74 a. Indentations (notshown) in the shield body 50 a and/or indentations (not shown) in mainbody 20 a may function as such an alignment orientation, as described inco-pending application Ser. No. 11/123,849, previously incorporated byreference.

Lancet 70 a further includes a carrier body 76 a supporting lancet 72 aat the rearward end thereof. The carrier body 76 a and shield body 50 amay include corresponding guiding surfaces for guiding the movement oflancet 70 a in shield body 50 a. For example, carrier body 76 a mayinclude guide tabs 78 a on an external surface thereof, with shield body50 a defining corresponding guide channels 80 a extending longitudinallyalong an inner surface thereof for accommodating guide tabs 78 aslidably therein. The carrier body 76 may include a pair of guide tabs78 a on opposing lateral sides thereof as illustrated, or a single guidetab 78 a, and shield body 50 a may include a corresponding pair of guidechannels 80 a extending along opposing inner surfaces thereofcorresponding to each of the guide tabs 78 a, or a single correspondingguide channel 80 a. It is contemplated that the arrangement of the guidetabs and channels 78 a, 80 a may be reversed, and multiple guidetabs-guide channels 78 a, 80 a (i.e., three or more) may also be used.The guide tabs 78 a and guide channels 80 a ensure that lancet 70 a isproperly aligned within shield body 50 a, and guides the sliding axialmovement of lancet 70 a within shield body 50 a and, further, may beused to prevent or resist rotational movement of carrier body 76 a inshield body 50 a. A distal facing surface 82 a on guide tabs 78 aengages shelves or wings 66 a on shearable element 62 a in the initialor pre-actuated state of lancet device 10 a until the shelves or wings66 a are broken to release lancet 70 a. The carrier body 76 a furthercomprises a proximal or rearward end spring guide 86 a and a distal orforward end spring guide 88 a for engaging a drive spring and retractionspring, respectively, of lancet device 10 a as described herein. Springguides 86 a, 88 a may be formed integral with the carrier body 76 a orbe provided as distinct, separate elements and secured to the body ofcarrier body 76 a by means customary in the medical field as, forexample, with medical grade adhesive or direct mechanical attachment.

Movement of the lancet 70 a through the lancet device 10 a is achievedthrough a biasing force provided by a drive spring 92 a. Drive spring 92a is adapted to exert a biasing force against lancet 70 a to drivelancet 70 a through the lancet device 10 a toward the puncturingposition, and is disposed between the rearward end of the housing 12 aand the lancet 70 a. Rear cap 24 a may include structure for alignmentof and/or for maintaining drive spring 92 a in the proper orientation onrear cap 24 a. For example, rear cap 24 a may include an internalalignment structure (not shown) for correctly positioning the drivespring 92 a. The lancet 70 a, as indicated previously, includes proximalspring guide 86 a which engages the opposite end of drive spring 92 a inthe initial or pre-actuated state of lancet device 10 a. In the initialstate of lancet device 10 a, drive spring 92 a extends between rear cap24 a and distal spring guide 86 a of carrier body 76 a. When the lancet70 a is in the initial, pre-actuated state, drive spring 92 a is in asubstantially unloaded, relaxed condition and exerts little to nobiasing force on lancet 70 a. Upon compressing or “loading” the drivespring 92 a, the lancet device 10 a is placed into an armed or loadedstate ready for a puncturing procedure as described in detail herein.

A retraction or return spring 94 a may further be provided at theforward or distal end of the lancet device 10 a, for retracting thelancet 70 a within the shield body 50 a after the lancet 70 a has moveddistally to the puncturing position wherein the puncturing element 74 aextends outward from the distal or forward end 54 a of shield body 50 aa sufficient distance to cause a puncture wound in the patient.Retraction spring 94 a is adapted to be engaged by distal spring guide88 a extending forward from carrier body 76 a during the forwardmovement of lancet 70 a, as described herein. The forward or distal endwall 58 a of shield body 50 a further comprises an axially rearward, orproximally-extending internal sleeve 96 a which defines a distal endpocket 98 for receiving retraction spring 94 a. The retraction spring 94a is disposed in distal end pocket 98 a throughout the operationsequence of lancet device 10 a in a puncturing procedure. The retractionspring 94 a may be secured in distal end pocket 98 a through use of amedical grade adhesive or by mechanically securing retraction spring 94a in distal end pocket 98 a. The drive and retraction springs 92 a, 94 aare typically compression springs capable of storing potential energywhen in a compressed state.

Lancet device 10 a may further include a protective tab or cover 100 afor protectively covering the forward end of the lancet 70 a and, inparticular, the puncturing end 74 a of lancet 72 a. The tab or cover 100a protectively covers puncturing end 74 a to maintain sterility thereofprior to use. The tab or cover 100 a is typically a relatively thin andelongated structure that extends from carrier body 76 a through theforward opening 60 a in shield body 50 a for grasping by a user of thelancet device 10 a. Tab or cover 100 a may be integrally formed with thebody of carrier body 76 a, for example, by being integrally formed withcarrier body 76 a during a plastic molding process. The connectionbetween tab or cover 100 a and carrier body 76 a may include a weakenedarea in the form of a perimeter groove or score line, along which thetab or cover 100 a is intended to break to remove the cover 100 a fromcarrier body 76 a. The tab or cover 100 a, as depicted, extends forwardfrom distal spring guide 88 a of carrier body 76 a. Tab or cover 100 ais sized to extend axially through retraction spring 94 a. Variousconfigurations of the tab or cover 100 a are described in co-pendingapplication Ser. No. 11/123,849, previously incorporated by reference.

The respective elements of the lancet device 10 a are all typicallyformed of molded plastic material, such as a medical grade plasticmaterial. The lancet 72 a may be constructed of any suitable materialadapted for puncturing the skin, and is typically a surgical grade metalsuch as stainless steel.

Use and actuation of lancet device 10 a will now be described withcontinued reference to FIGS. 1-6. Lancet device 10 a is typicallyinitially provided with cover 100 a extending distally from carrier body76 a, and through forward opening 60 a in the forward end wall 58 a ofshield body 50 a. In the initial, unarmed state of lancet device 10 a,the drive spring 92 a is substantially uncompressed (i.e., unloaded) andin a relaxed state. Drive spring 92 a extends from the inner side ofrear cap 24 a to the carrier body 76 a and, more particularly, isdisposed about proximal spring guide 86 a of carrier body 76 a. To usethe lancet device 10 a in a puncturing procedure, the drive spring 92 amust be compressed and placed into a compressed, armed state to providethe biasing force needed to move the lancet 70 a through housing 12 aand shield 14 a. Further, in the initial state, the drive spring 92 aacts on spring guide 86 a substantially only to position lancet 70 awithin main body 20 a of housing 12 a. More particularly, drive spring92 a positions carrier body 76 a at a relatively fixed and stationaryposition within main body 20 a of housing 12 a, wherein the lancet 70 aoccupies a generally fixed position relative to main body 20 a ofhousing 12 a and shield body 50 a of shield 14 a. Further, drive spring92 a acting on spring guide 86 a of carrier body 76 a positions thecarrier body 76 a such that guide tabs 78 a extending laterally fromcarrier body 76 a contact cantilevered shelves or wings 66 a onshearable element 62 a, which further serves to position shearableelement 62 a and shield body 50 a at a substantially fixed positionrelative to main body 20 a. In particular, the drive spring 92 a acts oncarrier body 76 a to position carrier body 76 a such that the distalsurface 82 a on guide tabs 86 a is in interference engagement withshelves 66 a, and positions the shearable element 62 a and shield body50 a at a generally fixed position relative to main body 20 a.Accordingly, until the user is ready to use the lancet device 10 a,shearable element 62 a and shield body 50 a are kept at a substantiallyconstant relative position with respect to main body 20 a.

To use the lancet device 10 a, the user grasps opposing sides of housing12 a, such as between a finger and thumb, and removes breakable cover100 a. Cover 100 a is removed typically by moving cover 100 a in acombined twisting and pulling motion in forward opening 60 a defined inforward end wall 58 a of shield body 50 a to break the frangibleconnection with carrier body 76 a. Once the frangible connection isbroken, the cover 100 a may be removed through the forward opening 60 a.The forward end wall 58 a of shield body 50 a may then be placed incontact with a location on the patient's body where it is desired tocause a puncture injury to initiate blood flow. If provided, targetindicia may be aligned with the desired location of puncture.

Once placed against the body, the user exerts a downwardly directedforce on main body 20 a of housing 12 a forcing shield body 50 a ofshield 14 a to retract (i.e., depress) into housing 12 a. In particular,the user applies a downward directed force in the direction of Arrow X,thereby applying a force against the user's body (i.e., skin surface).Such force establishes an opposing force on forward end wall 58 a ofshield body 50 a causing shield body 50 a to retract axially andproximally within main body 20 a of housing 12 a. As shield body 50 aretracts into main body 20 a, rearward end 54 a of shield body 50 amoves proximally (i.e., rearward) toward rear cap 24 a. The interferenceengagement between abutment recess 68 a on shearable element 62 a andthe rear rim 63 a at the rearward end 54 a of shield body 50 a causesshearable element 62 a to move in combination with shield body 50 atoward rear cap 24 a. Substantially simultaneously, the interferenceengagement between guide tabs 78 a and shelves or wings 66 a begins toexert compressive pressure or force on drive spring 92 a. In particular,as the user applies downward force on housing 12 a, shield body 50 a andshearable element 62 a move rearward and transmit the opposing force todrive spring 92 a through the interference engagement between distal endsurface 82 a on guide tabs 78 a and shelves 66 a, thereby beginning tocompress drive spring 92 a between rear cap 24 a and carrier body 76 a.

As the entire lancet 70 a continues to move rearward, the interferenceengagement between guide tabs 78 a and shelves 66 a compresses drivespring 92 a between rear cap 24 a and carrier body 76 a and, moreparticularly, between proximal spring guide 86 a and rear cap 24 a.While the shelves or wings 66 a are intentionally formed to be broken(i.e., frangible), the shelves 66 a are formed with sufficient strengthto withstand the force required to axially compress drive spring 92 abetween proximal spring guide 86 a and rear cap 24 a a pre-selecteddistance without breaking. Further downward movement of main body 20 aof housing 12 a eventually causes the proximal spring guide 86 a tocontact or “bottom out” against the inner side of rear cap 24 a. At thispoint, drive spring 92 a substantially reaches its maximum compressionbetween proximal spring guide 86 a and rear cap 24 a and the lancetdevice 10 a is now “armed” or “loaded” sufficiently to carry out apuncturing procedure. Optionally, spring guide 86 a does not need tocontact or “bottom out” against the inner side of rear cap 24 a, anddrive spring 92 a may have sufficient stored potential energy to carryout the actuation of lancet device 10 a.

Once the proximal spring guide 86 a contacts the inner side of rear cap24 a, continued downward force applied to main body 20 a of housing 12 ais applied entirely to breakable shelves or wings 66 a through theinterference engagement with guide tabs 78 a. In particular, once theproximal spring guide 86 a contacts rear cap 24 a, the user's entiredownward applied force is transmitted from main body 20 a (i.e., rearcap 24 a) to carrier body 76 a and, accordingly, guide tabs 78 a. Theinterference engagement between guide tabs 78 a and shelves 66 a focusesthe downward applied force on the shelves 66 a, which will cause theshelves 66 a to yield, shear, or break (i.e., fail) in a distal orforward direction at weakened area 67 a and into internal cavity 56 a ofshield body 50 a. At the moment the shelves or wings 66 a break, therestraining or compression force previously applied to drive spring 92 adue to the interference engagement between guide tabs 78 a and shelves66 a is released, releasing the stored potential energy in drive spring92 a to allow the drive spring 92 a to move lancet 70 a forward inshield body 50 a. Additionally, with the interference engagement brokenbetween the guide tabs 78 a and shelves 66 a removed, the shearableelement 62 a and shield body 50 a are free to retract rearward to engageannular rim 36 a on rear cap 24 a where their further rearward movementthereof is halted. As the shearable element 62 a and shield body 50 amove toward annular rim 36 a, shearable element 62 a rides over top ofannular ridge 40 a on the inner surface of main body 20 a of housing 12a. The engagement of shearable element 62 a with annular ridge 40 aincreases the frictional engagement between the shearable element 62 aand main body 20 a of housing 12 a, thereby substantially fixing theposition of shearable element 62 a and shield body 50 a relative to mainbody 20 a and inhibiting the shield body 50 a from moving forward againin main body 20 a. The frictional engagement between the outer surfaceof shearable element 62 a and annular ridge 40 a operates substantiallyas a frictional lock or brake to substantially prevent forward movementof shield body 50 a in main body 20 a after the shearable element 62 aand shield body 50 a retract fully into main body 20 a and engage rearcap 24 a.

With the stored potential energy in compressed drive spring 92 areleased, the drive spring 92 a biases the lancet 70 a away from rearcap 24 a and through internal cavity 56 a in shield body 50 a. Inparticular, with the interference engagement between guide tabs 78 a andshelves 66 a removed, the biasing force of drive spring 92 a propelslancet 70 a downward and distally away from the rear cap 24 a axiallythrough main body 20 a of housing 12 a and shield body 50 a of shield 14a. During such movement, corresponding guide tabs 78 a and guidechannels 80 a guide lancet 70 a axially through shield body 50 a. Thebiasing force acting on lancet 70 a is preferably sufficient to causethe puncturing end 74 a of lancet 72 a to project a sufficient distanceand with sufficient kinetic energy from the forward opening 60 a inshield body 50 a to cause a puncture wound in the desired location on apatient's body. Moreover, during the propelling movement of lancet 70 a,proximal spring guide 86 a on carrier body 76 a of lancet 70 a releasesfrom drive spring 92 a which remains connected to rear cap 24 a.

Further, as the lancet 70 a moves forward in the propelling movement,distal spring guide 88 a engages the rearward end of retraction spring94 a. The biasing force provided by drive spring 92 a is at least inpart applied to retraction spring 94 a by engagement of distal springguide 88 a with the rearward end of retraction spring 94 a which causesthe retraction spring 94 a to compress toward distal end pocket 98 a.The retraction spring 94 a is designed such that it may be compressed inwhole or in part by the biasing force of drive spring 92 a propellinglancet 70 a, but still permits puncturing end 74 a of lancet 72 a toextend through forward opening 60 a in shield body 50 a a sufficientdistance and with sufficient force to puncture the skin of the patientand initiate blood flow. Distal spring guide 88 a is sized to provide anabutment surface for abutting against internal sleeve 96 a supportingretraction spring 94 a to prevent lancet 70 a from axial movemententirely out of shield body 50 a through forward or front opening 60 a.

As indicated previously, retraction spring 94 a is typically acompression spring and will have sufficient resilience to return to arelaxed, unloaded state within shield body 50 a after the lancet 70 aextends to the puncturing position. Accordingly, once the retractionspring 94 a is compressed it will provide a return biasing force on thelancet 70 a by engagement with the distal spring guide 88 a on carrierbody 76 a. The retraction spring 94 a thereby acts between the forwardend wall 58 a of the shield body 50 a and distal spring guide 88 a oncarrier body 76 a to cause sufficient or complete retraction of thelancet 70 a into shield body 50 a. In particular, retraction spring 94 aapplies a return biasing force that retracts the puncturing end 74 a oflancet 72 a entirely within shield body 50 a. Moreover, as theretraction spring 94 a returns to a relaxed or unloaded state withinshield body 50 a, the lancet 70 a is returned to a static positionwithin shield body 50 a, wherein lancet 70 a is disposed at a relativelyfixed and stationary position within shield body 50 a. Once retractionspring 94 a returns to a relaxed or uncompressed state, the retractionspring 94 a maintains the lancet 70 a disposed within the shield body 50a with puncturing end 74 a shielded within shield body 50 a, andpreventing further movement of lancet 70 a to the puncturing position.The lancet device 10 a is therefore safely protected from re-use and maybe properly discarded, such as in an appropriate medical wastecontainer.

Referring to FIGS. 7-12, a second embodiment of a lancet device 10 b isgenerally illustrated, and comprises the same basic components as lancetdevice 10 a described previously. Generally, lancet device 10 bcomprises a housing 12 b, a shield 14 b movably associated with thehousing 12 b, and a lancet 70 b movably disposed in housing 12 a andmovable through shield 14 b. As the foregoing basic components of lancetdevice 10 b are substantially similar to the corresponding components oflancet device 10 a, only distinct differences between these componentswill be discussed herein, along with the use and sequence of operationof lancet device 10 b.

In contrast to lancet device 10 a, lancet device 10 b does not comprisea structure corresponding to shearable element 62 a discussedpreviously. Lancet device 10 b comprises the shield 14 a having a shieldbody 50 b with a rear ledge or rim 102 at shield proximal end 54 b. Therear ledge or rim 102 is adapted for interference engagement withforward rim 42 b at the forward end portion 22 b of main body 20 a ofhousing 12 a. The interference engagement of rear ledge 102 with forwardrim 42 b is provided to prevent the shield body 50 b from axiallysliding completely out of housing 12 b through front opening 30 bdefined in forward rim 42 b prior to actuating lancet device 10 b. Rearrim 102 is sized such that it may contact and slidably engage the innersurface of main body 20 b when shield body 50 b is retracted (i.e.,depressed) into main body 20 b, as will occur when the lancet device 10b is actuated by a user.

A further difference over lancet device 10 a discussed previously liesin the interfering structure between lancet 70 b and shield 14 b used toplace lancet device 10 b into an armed or loaded state, and thereaftercause actuation of lancet device 10 b. In lancet device 10 b, shieldbody 50 b comprises inward-extending shelves, wings, or internal tabs104, which take the place of breakable shelves or wings 66 a onshearable element 62 a in lancet device 10 a. The internal tabs 104 aredesirably formed integrally with the shield body 50 b, but may also bepart of an additional, separate structure associated with shield body 62a, for example associated with rear rim 102 and extending into centralcavity or bore 56 b of shield body 50 b. While shield body 50 b is shownwith two opposing and inward-extending internal tabs 104, it will beappreciated that only one internal tab 104 is necessary for engagementwith the lancet 70 b in a similar manner to that described previously inconnection with the breakable shelves or wings 66 a on shearable element62 a.

In lancet device 10 a, guide tabs 78 a form the structure on lancet 70 afor an interference engagement with breakable shelves or wings 66 a,which initially just contact shelves 66 a under the position effect ofdrive spring 92 a in the initial or pre-actuated state of lancet device10 a. In lancet device 10 b, guide tabs 78 b are further provided orformed with cutting elements 106 which may be cutting blades, edges, andthe like. Cutting elements 106 may be formed integrally with guide tabs78 b or, alternatively, be separate cutting structures secured to guidetabs 78 b by means customary in the medical device field, such as directmechanical or adhesive attachment. The cutting elements 106 are adaptedto cut, shear, or plastically deform internal tabs 104 in the internalcavity 56 b of shield body 50 b during actuation of lancet device 10 bto permit movement of lancet 70 b through shield body 50 b, and therebyconduct a puncturing procedure. Other than the foregoing structuraldifferences, lancet device 10 b is substantially similar in all otherrespects to the structure of lancet device 10 a described previously.

With continued reference to FIGS. 7-12, use and operation of lancetdevice 10 b will now be discussed. Prior to use, cover 100 b extendingdistally from carrier body 76 b is removed by breaking the frangibleconnection with carrier body 76 b in the manner described previously andwithdrawing cover 100 b from forward opening 60 b in forward end wall 58b of shield body 50 b. The forward end wall 58 b of shield body 50 b maythen be placed in contact with a target location on a patient's body. Inthe initial state of lancet device 10 b, the drive spring 92 b issubstantially uncompressed (i.e., unloaded) and in a relaxed state.Drive spring 92 b extends from proximal spring guide 86 a of carrierbody 76 a to rear cap 24 b. As discussed previously, in the initialstate of lancet device 10 b, drive spring 92 a is in a relaxed conditionand acts on spring guide 86 b substantially to position lancet 70 b at astationary position within main body 20 b of housing 12 a, wherein thelancet 70 b occupies a generally fixed position relative to main body 20b. Additionally, drive spring 92 b acts on spring guide 86 b on carrierbody 76 b to position carrier body 70 a in main body 20 b such thatguide tabs 78 b and more particularly, cutting elements 106 are ininterference engagement with tabs or shelves 104 in the internal cavity56 b of shield body 50 b. The interference engagement between cuttingelements 106 and internal tabs 104 further operates to place shield body50 b at a generally fixed and stationary position relative to main body20 b. Accordingly, until the user is ready to use lancet device 10 b,shield body 50 b is kept substantially at a generally fixed andstationary position relative to main body 20 a by virtue of theinterference engagement between guide tabs 78 b and internal tabs 104 inshield body 50 b.

To use the lancet device 10 b, the user grasps opposing sides of housing12 b and exerts downwardly directed force on main body 20. This forcecauses an opposing force on forward end wall 58 b of shield body 50 b,causing shield body 50 b to retract axially within main body 20 a. Asshield body 50 b retracts into main body 20 b, rearward end 54 a ofshield body 50 a moves proximally (i.e., rearward) toward rear cap 24 b.Due to the interference engagement between guide tabs 78 b and internaltabs or shelves 104 and, more particularly, between cutting elements 106on guide tabs 78 b and internal tabs or shelves 104, lancet 70 b alsomoves rearwardly toward rear cap 24 b. As the shield body 50 b movesrearward, the opposing force is applied to drive spring 92 b through theinterference engagement between cutting elements 106 on guide tabs 78 aand internal tabs or shelves 104, thereby compressing drive spring 92 bbetween rear cap 24 b and carrier body 76 b. While internal tabs 104 areintended to cut-through or plastically deformed by cutting elements 106,they are formed with sufficient strength to withstand being cut-throughor sheared-off by cutting elements 106 under the opposing force requiredto axially compress drive spring 92 b between proximal spring guide 86 band rear cap 24 b. In other words, internal tabs or shelves 104 areformed to withstand the force required to compress drive spring 92 b apredetermined distance prior to the desired point of triggering. Furtherdownward movement of housing 12 b eventually causes proximal springguide 86 b to contact the inner side of rear cap 24 a. At this point,drive spring 92 ba substantially reaches its maximum compression with amaximum level of stored potential energy. Lancet device 10 b is now inan armed or loaded state sufficient to carry out a puncturing procedure.

Once the proximal spring guide 86 b contacts rear cap 24 b, the downwardforce applied to main body 20 b of housing 12 b is applied entirely tothe interference engagement between cutting elements 106 and internaltabs 104. In particular, once proximal spring guide 86 b contacts rearcap 24 b, the user's entire downward applied force is transmitted frommain body 20 b (i.e., rear cap 24 b) to carrier body 76 b and,accordingly, guide tabs 78 b and cutting elements 106. The downwardcutting force on the internal tabs 104 is now sufficient to cut-throughor plastically deform internal tabs 104. At the moment the internal tabs104 are cut-through or plastically deformed, the opposing force appliedto compress drive spring 92 b is released, thereby allowing drive spring92 b to move lancet 70 b forward in shield 14 b. Additionally, with theinterference engagement between guide tabs 78 b and internal tabs 104removed, shield body 50 b is able to retract further rearward under thedownward force still typically applied by the user to housing 12 b. Theshield body 50 b ultimately moves rearward to a position engagingannular rim 36 b on rear cap 24 b where further rearward movement ishalted. As the shield body 50 b moves toward annular rim 36 b on rearcap 24 b, rear rim 102 on the rearward end 54 b of shield body 50 brides over top of annular ridge 40 b. The annular ridge 40 b thereafterforms a locking structure to inhibit or prevent subsequent forwardmovement of shield 50 b.

With the potential energy stored in drive spring 92 b by compressionthereof released, the drive spring 92 b biases lancet 70 b away fromrear cap 24 b and through shield body 50 b. During such propellingmovement, the corresponding guide tabs 78 b and guide channels 80 bguide lancet 70 b axially through shield body 50 b. The biasing forceapplied to lancet 70 a is preferably sufficient to cause the puncturingend 74 b of lancet 72 b to project a sufficient distance and withsufficient force from the forward opening 60 b in shield body 50 b tocause a puncture wound at the target location on the patient's body.Moreover, during the propelling movement of lancet 70 b, proximal springguide 86 b on carrier body 76 b releases from drive spring 92 b whichremains connected to rear cap 24 b. Internal sleeve 96 b at the forwardend wall 58 b defines a distal stop for engaging distal spring guide 88b and prevents lancet 70 b from axial movement entirely out of shieldbody 50 b through forward opening 60 b.

As the lancet 70 b moves forward in the propelling movement, distalspring guide 88 b engages retraction spring 94 b. The biasing forceapplied to lancet 70 b by drive spring 92 b is at least in part appliedto retraction spring 94 b by engagement of distal spring guide 88 b withretraction spring 94 b, which causes the retraction spring 94 b tocompress toward distal end pocket 98 b. The retraction spring 94 apermits puncturing end 74 b of lancet 72 b to extend through forwardopening 60 b in shield body 50 b a sufficient distance and withsufficient kinetic energy to puncture the skin of the patient andinitiate blood flow, and thereafter return lancet 70 b to asubstantially fixed and stationary position within shield 14 b. Inparticular, as the retraction spring 94 b returns to a relaxed orunloaded state within shield body 50 b, the lancet 70 a is retracted inshield 14 b and returned to a substantially fixed and stationarypositioned within shield body 14 b. Thereafter, the engagement ofretraction spring 94 b with distal spring guide 88 b maintains thelancet 70 b at a generally fixed and stationary position within shieldbody 50 b. This maintains puncturing end 74 b shielded within shieldbody 50 b, and prevents further movement of lancet 70 b to thepuncturing position.

Referring to FIGS. 13-18, a third embodiment of a lancet device 10 c isgenerally illustrated, and comprises the same basic components as lancetdevices 10 a, 10 b described previously. Generally, lancet device 10 ccomprises a housing 12 c, a shield 14 c movably associated with thehousing 12 c, and a lancet 70 c movably disposed in housing 12 c. As theforegoing basic components of lancet device 10 c are substantiallysimilar to the corresponding components of lancet devices 10 a, 10 bonly distinct differences between these components will be discussedherein, along with the general use and sequence of operation of lancetdevice 10 c.

In lancet devices 10 a, 10 b, lancets 70 a, 70 b are initiallypositioned at substantially fixed and stationary positions in housings12 a, 12 b by drive springs 92 a, 92 b in the initial, pre-actuatedstates of these devices. In lancet devices 10 a, 10 b, drive springs 92a, 92 b are initially in a relaxed, unloaded condition and act uponlancets 70 a, 70 b to position lancets 70 a, 70 b relative to housings12 a, 12 b. Lancet devices 10 a, 10 b are only placed in an armed orloaded state when shields 14 a, 14 b are retracted (i.e., depressed)into housings 12 a, 12 b under the force applied by a user, which inturn causes lancets 70 a, 70 b to act upon drive springs 92 a, 92 b andcompress and load the respective drive springs 92 a, 92 b with potentialenergy.

Lancet device 10 c is initially provided in an armed or loaded state,with lancet 70 c ready to be biased to a puncturing position by acompressed drive spring 92 c. In this initial armed state, drive spring92 c is in a compressed (i.e., loaded) state, ready to bias the lancet70 c through a puncturing procedure upon release. In particular, lancetdevice 10 c is provided with drive spring 92 c compressed betweenproximal spring guide 86 c on carrier body 76 c and rear cap 24 c. Thelancet 70 c is secured against forward movement into shield 14 c by alocking or actuation structure 110 extending between housing 12 c andlancet 70 c. Actuator 110 prevents release of lancet 70 c and,correspondingly, maintains compression of drive spring 92 c until a userof the lancet device 10 c is ready to carry out a puncturing procedure.

Actuator 110 generally comprises a sleeve portion 112 and one or morepivotal splints or tabs 114, for example elastic splints, extending fromthe sleeve portion 112. Sleeve portion 112 is disposed in an annularwall recess 116 defined in the inner surface of main body 20 c ofhousing 12 c. Main body 20 c is formed with a generally thicker annularwall in lancet device 10 c in comparison to lancet devices 10 a, 10 b.Sleeve portion 112 may be secured in wall recess 116 by a medical gradeadhesive and/or preferably by being captured axially between wall recess116 and annular rim 36 c on rear cap 24 c and thereby frictionally heldin wall recess 116. Actuator 110 is depicted with two generallyinward-extending splints or tabs 114 engaging lancet 70 c. While thisconfiguration is desirable, only one elastic splint 114 for engaginglancet 70 c is typically required, and additional splints 114 in excessof two may be also be provided.

The splints 114 extend generally rearward or in a proximal direction inmain body 20 c and engage guide tabs 78 c on carrier body 76 c of lancet70 c. Splints 114 are angled inward, in this instance, at approximatelya 45° angle relative to Central Axis A to engage guide tabs 76 c in theinitial state of lancet device 10 c. In particular, ends 118 of splints114 engage guide tabs 78 c on carrier body 76 c to prevent lancet 70 cfrom releasing from the initial, armed state of lancet device 10 c andthereby maintain drive spring 92 c in a compressed state until lancetdevice 10 c is actuated by a user. Splints 114 are each connected by ahinge connection 120 to sleeve portion 112. The hinge connection 120 maybe a living hinge as illustrated as an exemplary embodiment of thisstructure. Ends 118 of splints 114 engage a corner of guide tabs 78 c,such that distal movement of carrier body 76 c distally with respect tohousing 12 c in absence of shield 14 c would cause splints 114 togenerally compress between hinge connection 120 and the point of contactbetween guide tabs 78 c. As with lancet devices 10 a, 10 b, lancetdevice 10 c is actuated when a user depresses housing 12 c to retract(i.e., depress) shield 14 c therein. However, shield 14 c is now adaptedto release actuator 110 between housing 12 c and lancet 70 c, therebyreleasing compressed drive spring 92 c to bias the lancet 70 c through apuncturing procedure.

To facilitate actuation of lancet device 10 c, shield 14 c is adapted toengage and release actuator 110. For this purpose, shield body 50 c maybe formed with a tapered rear rim 122 at shield proximal end 54 c. Thetapered rear rim 120 is generally tapered in the same direction assplints 114 to engage the distal or forward facing sides of splints 114.The point of engagement for the tapered rear rim 122 is on splints 114at a location between hinge connection 120 and the point of contactbetween guide tabs 78 c. The tapered rear rim 122 may define a taper ofabout 45° to correspond to the inward taper of splints 114. In theinitial, armed state of lancet device 10 c, the tapered rear rim 122 isin contact with splints 114 so that any rearward movement of shield 14 cinto housing 12 a will immediately act upon the actuator 110 and splints114 in particular. While the rear rim 122 is illustrated with a definedtaper, it will be appreciated that such taper may be omitted and shieldbody 50 c formed as a cylindrical structure with a flat or blunted rearrim 122.

With continued reference to FIGS. 13-18, use and operation of lancetdevice 10 c will now be discussed. As with previous embodiments, cover100 c extending distally from carrier body 76 c is first removed bybreaking the frangible connection with carrier body 76 c and withdrawingcover 100 c from forward opening 60 c in forward end wall 58 c of shieldbody 50 c. The forward end wall 58 c of shield body 50 c may then beplaced in contact with the target location on the patient's body. Asindicated, lancet device 10 c is initially provided in an armed statewith lancet 70 c ready to initiate a puncturing procedure whencompressed drive spring 92 c is released.

To carry out a puncturing procedure, the user grasps opposing sides ofhousing 12 c and exerts downwardly directed force in the direction ofArrow X on main body 20 c forcing shield body 50 c to retract into mainbody 20 c. This force causes an opposing force on forward end wall 58 cof shield body 50 c, causing shield body 50 c to retract axially withinmain body 20 c. As shield body 50 c retracts into main body 20 c,tapered rear rim 122 on rearward end 54 c of shield body 50 c and inengagement with splints 114 begins to move splints 114 radially outwardtoward sleeve portion 112. Continued rearward movement of shield body 50c causes the splints 114 to continue their radial outward movement awayfrom lancet 70 c until the splints 114 disengage from guide tabs 78 cand release the interference engagement therewith. The configuration ofactuator 110 converts the axial movement of shield body 50 c intopivotal radial outward movement of splints 114 to effectuate actuationof lancet device 10 c.

With the potential energy in drive spring 92 c released, drive spring 92c biases the lancet 70 c away from rear cap 24 c and through shield body5 cb. During such propelling movement, corresponding guide tabs 78 c oncarrier body 76 c and guide channels 80 c within shield body 50 c guidelancet 70 c axially through shield body 50 c. The biasing force impartedto lancet 70 c is preferably sufficient to cause the puncturing end 74 cof lancet 72 c to project a sufficient distance and with sufficientforce from the forward opening 60 c of shield body 50 c to cause apuncture wound in the desired location on the patient's body. Moreover,during the propelling movement of lancet 70 c, proximal spring guide 86c on carrier body 76 c releases from drive spring 92 c which remainsconnected to rear cap 24 c. Distal spring guide 88 c provides anabutment surface for engaging internal sleeve 96 c supporting retractionspring 94 c to prevent lancet 70 c from axial movement entirely out ofshield body 50 c through forward opening 60 c.

As the lancet 70 c moves forward in the propelling movement, distalspring guide 88 c engages retraction spring 94 c. The biasing/propellingforce provided by drive spring 92 c is at least in part applied toretraction spring 94 c by engagement of distal spring guide 88 c withretraction spring 94 c, which causes the retraction spring 94 c tocompress toward distal end pocket 98 c. The retraction spring 94 cpermits puncturing end 74 c of lancet 72 c to extend through forwardopening 60 c in shield body 50 c a sufficient distance and withsufficient force to puncture the skin of the patient and initiate bloodflow, and thereafter return lancet 70 c to a substantially fixed andstationary position within shield 14 b. In particular, as the retractionspring 94 c returns to a relaxed or unloaded state within shield body 50c, the lancet 70 c is retracted in shield 14 c and returned to agenerally stationary and fixed position within shield body 50 c.Thereafter, the engagement of retraction spring 94 c with distal springguide 88 c maintains the lancet 70 c at a stationary and relativelyfixed position within shield body 50 c and maintains puncturing end 74 cshielded within shield body 50 c preventing further movement of lancet70 c to the puncturing position.

Referring to FIGS. 19-23, a fourth embodiment of a lancet device 10 d isgenerally illustrated, and generally comprises a housing 12 d and alancet 70 d disposed in housing 12 d. Lancet device 10 d differs fromlancet devices 10 a-c discussed previously, as lancet device 10 d is notactuated through the retraction (i.e., depression) of a shield elementinto housing 12 d. However, lancet device 10 d is similar to lancetdevice 10 c discussed immediately above because lancet device 10 d isinitially provided in an armed or loaded state, with lancet 70 d readyto be biased to the puncturing position by drive spring 92 d uponrelease of an interfering structure. In this initial, armed state, drivespring 92 d is in a compressed (i.e., loaded) state, ready to bias thelancet 70 d through a puncturing procedure upon repositioning lancet 70d with respect to an interfering structure or engagement between housing12 d and lancet 70 d. However, the configuration of the housing 12 d,lancet 70 d, and drive spring 92 d differ from previous embodiments andthese differences will now be described.

Housing 12 d of lancet device 10 d comprises an elongated main body 20 dthat generally defines a cylindrical and hollow configuration. The mainbody 20 d has a distal or forward end portion 22 d, and a rear cap 24 dforming a proximal or rearward end portion 26 d of the main body 20 d.The interior of housing 12 d is generally open and comprises an internalcavity 28 d. The internal cavity 28 d is closed at the rearward end dueto rear cap 24 d, and includes a front opening 30 d defined in forwardend portion 22 d of main body 20 d, and through which lancet 70 d atleast partially extends when lancet device 10 d is actuated. Main body20 d and rear cap 24 d may be integrally formed. Typically, main body 20d and rear cap 24 d are separate elements that are affixed together toform housing 12 d, as illustrated, which facilitates assembly of lancetdevice 10 d. As examples, main body 20 d and rear cap 24 d may beaffixed together through an appropriate medical grade adhesive, and/ormay be connected using inter-engaging structures providing a mechanicalengagement therebetween, such as a friction-fit or a snap-fitconstruction. For example, main body 20 d may include an annular rim 32d defining an annular groove 34 d, and the rear cap 24 a may include amating annular rim 36 d having a mating annular lip 38 d as matingelements in much the same manner as described previously.

In contrast to previous embodiments, distal or forward end portion 22 dof main body 20 d comprises an axially rearward-extending internalsleeve 98 d that defines a distal end pocket 98 d for receiving andsupporting retraction spring 94 d. In previous embodiments, theretraction spring(s) were disposed in a distal end pocket formed as partof the forward end wall of the actuating shield structure. Thisstructure is now provided at the forward end portion 22 d of main body20 d of housing 12 d. Additionally, main body 20 d of housing 12 dfurther comprises an actuation structure or actuator 130 for causingactuation of lancet 70 d and corresponding release of drive spring 92 d.Actuator 130 generally comprises an actuating button or lever 132 thatis typically pivotally associated with main body 20 d. The pivotalassociation with main body 20 d may be in the form of a living hinge orequivalent structure and lever 132 may thus be integrally formed withmain body 20 d. A tab member 134 depends from an inner side of actuatinglever 132 for engaging lancet 70 d and causing actuation of the same. Inparticular, lever 132 is pivotally connected to main body 20 d so thatthe lever 132 may be depressed inward into internal cavity 28 d in mainbody 20 d, such that tab member 134 interacts with lancet 70 d to causeactuation or release of lancet 70 d.

Main body 20 d of housing 12 d includes opposing inner sidewalls 136each defining an internal guide channel 138 for guiding movement oflancet 70 d within main body 20 d. Guide channels 138 may be formed asgrooves or recesses in the inner sidewalls 136, or be formed in astructure extending inward from the respective sidewalls 136. Guidechannels 138 are generally L-shaped and comprise a longitudinallyextending main channel 140 and a generally transversely extending sidechannel 142. Main channel 140 extends distally forward from an areaproximate to tab member 134 to a location proximate to retraction spring94 d. Main channel 140 defines an abutment surface or stop 144 in guidechannels 138 to provide a stop for carrier body 76 d of lancet 70 d toprevent axial movement of the lancet 70 d entirely out of main body 20 dthrough front opening 30 d.

Side channel 142 is contiguous with main channel 140 and extendsapproximately oblique to transverse to main channel 140. Side channel142 extends upward in a direction towards lever 132. While side channel142 is formed generally oblique to main channel 140, side channel 142and main channel 140 define a tapered corner or vertex 146 at theirintersection. The corner 146 defines an angle of less than about 90°.The opposing side channels 142 in main body 20 d are used to initiallyreceive guide tabs 78 d on carrier body 76 d for maintaining carrierbody 76 d in a dynamically stable and balanced position, therebyopposing the force acting on guide tabs 78 d by drive spring 92 d, andrestraining compressed drive spring 92 d. Corner 146 is used to definethe transition between main channel 140 and side channel 142. Movementof guide tabs 78 d towards side channels 142 allows carrier body 76 d totransition from a position of dynamic stability to a position of dynamicinstability. Accordingly, side channels 142 initially maintain thepositioning of guide tabs 78 d, with guide tabs 78 d in interferenceengagement with corners or vertexes 146 to maintain the positioning ofguide tabs 78 d until lancet device 10 d is to be actuated.

Lancet 70 d is formed in a generally analogous manner as previousembodiments and comprises a lancet 72 d with a puncturing end 74 d atthe forward end thereof, and a carrier body 76 d supporting lancet 72 dat the rearward end thereof. The carrier body 76 d comprises a pair ofguide tabs 78 d on an external surface thereof that engage guidechannels 138. Lancet 70 d is adapted for axial movement through theinternal cavity 28 d of main body 20 d between an initial positionwherein guide tabs 78 d are disposed in side channels 142 and thepuncturing end 74 a is disposed entirely within main body 20 d, to apuncturing position wherein the puncturing end 74 d extends beyond thefront opening 30 d in main body 20 d a sufficient distance to cause apuncture wound on a patient's body while guide tabs 78 d remain disposedin main channels 140. Further details regarding the operation of lancetdevice 10 d and the movement of lancet 70 d are provided hereinafter.

Carrier body 76 d further comprises a proximal or rear rim 148 at therearward end thereof. Rim 148 defines the forward end of proximal springguide 86 d and typically has a diameter larger than the diameter ofdistal spring guide 88 d of carrier body 76 d. Rim 148 is provided as acontact structure or surface on lancet 70 d for engagement by tab member134 to cause actuation of lancet device 10 d. The diameter of rim 148 isalso typically sized to be at least equal to the diameter of drivespring 92 d and provides a contact structure or surface that restrainscompressed drive spring 92 d in the initial state of lancet 70 d. Duringactuation of lancet device 10 d, drive spring 92 d acts against rear rim148 to bias lancet 70 d to the puncturing position, as described herein.Moreover, carrier body 76 d additionally comprises two opposing posts150 cooperating with guide channels 138, and main channels 140 inparticular. Posts 150 engaged in guide channels 138 permit at least alimited amount of pivotal movement by carrier body 76 d about an axispassing through posts 150, and maintain lancet 70 d associated withguide channels 138 until guide tabs 78 d align with main channels 140during the actuation sequence of lancet device 10 d.

In the initial state of lancet device 10 d, drive spring 92 d is atleast partially compressed between rear rim 148 on carrier body 76 d andrear cap 24 d, and typically has sufficient stored potential energy toconduct a skin-puncturing procedure. The rearward or proximal end ofdrive spring 92 d is typically secured to rear cap 24 d in the mannerdiscussed previously in this disclosure. The forward or distal end ofdrive spring 92 d is associated with carrier body 76 d and may besecured to rear rim 148 by similar means discussed previously, as bysuitable adhesive or direct mechanical attachment. Drive spring 92 dgenerally defines an off-axis or off-center spring arrangement, whereindrive spring 92 d extends at upward angle toward lever 132. Drive spring92 d is stabilized in the off-center and compressed (i.e., loaded)arrangement by engagement of guide tabs 78 d in side channels 142 ofguide channels 138. Corners 146 define an interfering engagement andpoint of transition for guide tabs 78 d to maintain drive spring 92 d ina compressed (i.e., loaded) state and in the off-center configuration.The acute angle defined by corner 146 defines a receiving notch 152 forguide tabs 78 d to prevent guide tabs 78 d from readily releasing fromside channels 142 until intended actuation by a user. Thus, engagementof guide tabs 78 d in guide channels 138 forms an interfering structureto secure lancet 70 d against forward movement in main body 20 d and,correspondingly, maintains compression of drive spring 92 d until a userof the lancet device 10 d is ready to carry out a puncturing operation.

With continued reference to FIGS. 19-23, use and operation of lancetdevice 10 d will now be discussed. As with previous embodiments, a cover(not shown) extending distally from carrier body 76 d may be providedwith carrier body 76 d. As with previous embodiments, such a cover isremoved by breaking the frangible connection with carrier body 76 d andwithdrawing the cover from front opening 30 d in main body 20 d. Theforward end rim 42 d of main body 20 d may then be placed in contactwith the target location on a patient's body. As indicated previously,lancet device 10 d is initially provided in an armed state with lancet70 d ready initiate a puncturing procedure when compressed drive spring92 d is released.

To carry out a puncturing procedure, the user grasps opposing sides ofhousing 12 d and exerts downwardly directed force on lever 132 pivotallyconnected to main body 20 d, causing lever 132 to depress into internalcavity 28 d of main body 20 d. As lever 132 is depressed into main body20 d, tab member 134 interacts with rear rim 148 on carrier body 76 d.In particular, the downward force applied to lever 132 causes tab member134 to move rear rim 148 downward in the internal cavity 28 d. As rearrim 148 of carrier body 76 d moves downward in internal cavity 28 d ofmain body 20 d, the carrier body 76 d will substantially simultaneouslypivot about posts 150 in main channel 140 of guide channels 138. Alsosubstantially simultaneously, guide tabs 78 d received in side channels142 slide downward in side channels 142 until passing corners 146 whichhas the effect of moving carrier body 76 d from a first state of beingdynamically balanced to a second state of being dynamically unbalanced,thereby allowing drive spring 92 d to propel carrier body 76 d throughmain body 20 d until the puncturing end 74 d of lancet 72 d projectsthrough front opening 30 d in main body 20 d. The downward movement ofguide tabs 78 d in side channels 142 has the optional effect of furthercompressing drive spring 92 d.

As the lever 132 is continued to be depressed into main body 20 d, guidetabs 78 d eventually clear corners 146 and disengage from side channels142. At this point, guide tabs 78 d align with main channel 140 of guidechannels 138 and are free to move forward therein under the biasingforce of drive spring 92 d. Correspondingly, with the engagement betweenguide tabs 78 d and corners 146 released, the drive spring 92 d is freeto bias lancet 70 d to the puncturing position. With the storedpotential energy in drive spring 92 d released, drive spring 92 dthereafter biases the lancet 70 d away from rear cap 24 d and throughmain body 20 d. During such propelling movement, the engagement of guidetabs 78 d in guide channels 138 guides lancet 70 d axially through mainbody 20 d. The distal biasing energy imparted to lancet 70 d ispreferably sufficient to cause the puncturing end 74 d of lancet 72 d toproject a sufficient distance and with sufficient force from the frontopening 30 d in main body 20 d to cause a puncture wound in the desiredlocation on the patient's body. Moreover, during the propelling movementof lancet 70 d, proximal spring guide 86 d on carrier body 76 d releasesfrom drive spring 92 d which remains connected to rear cap 24 d. Theengagement of posts 150 with stops 144 in guide channels 138 preventslancet 70 d from axial movement entirely out of main body 20 d throughfront opening 30 d.

As the lancet 70 d moves forward in the propelling movement, distalspring guide 88 d engages retraction spring 94 d. The biasing force ofdrive spring 92 d is at least in part applied to retraction spring 94 dby engagement of distal spring guide 88 d with retraction spring 94 d,which causes the retraction spring 94 d to compress toward distal endpocket 98 d. The retraction spring 94 d permits puncturing end 74 d oflancet 72 d to extend through front opening 30 d in main body 20 d asufficient distance and with sufficient force to puncture the skin ofthe patient and initiate blood flow, and thereafter return lancet 70 dto a generally fixed and stationary position within housing 12 d. Inparticular, as the retraction spring 94 d returns to a relaxed orunloaded state within main body 20 d, the lancet 70 d is retracted inmain body 20 d and returned to a generally fixed and stationary positionwithin main body 20 d. Thereafter, the engagement of retraction spring94 d with distal spring guide 88 d maintains the positioning of lancet70 d within main body 20 d with puncturing end 74 d of lancet 72 dshielded within housing 12 d, and prevents further movement of lancet 70d to the puncturing position.

Referring to FIGS. 24-30, a fifth embodiment of a lancet device 10 e isgenerally illustrated, and comprises the same basic components orelements as lancet devices 10 a-c described previously. Generally,lancet device 10 e comprises a housing 12 e, a shield 14 e movablyassociated with the housing 12 e, and a lancet 70 e movably disposed inhousing 12 e. As the basic components of lancet device 10 e aresubstantially similar to the corresponding components of lancet devices10 a-c discussed previously, only distinct differences between thesegeneral components will be discussed herein, along with the use andsequence of operation of lancet device 10 e.

The sequence of operation of lancet device 10 e generally follows thesequence of operation of lancet devices 10 a-c, wherein lancet device 10e is armed and actuated through the retraction (i.e., depression) ofshield 14 e into housing 12 e. Generally, in lancet device 10 e, armingand actuation of lancet device 10 e occurs as a result of proximal orrearward end 54 e of shield body 50 e of shield 14 e engaging astructure within housing 12 e that causes compression (i.e., loading) ofdrive spring 92 e and, upon release of such compression, drive spring 92e biases lancet 70 e through a propelling movement resulting inpuncturing end 74 e of lancet 72 e projecting from shield 14 e forpuncturing procedure the skin of a patient, as discussed in more detailherein.

In lancet device 10 e, shield 14 e comprises a shield body 50 e with arear ledge or rim 162 at shield proximal end 54 e. The rear ledge or rim162 is generally adapted for contact or engagement with a slide plate164 disposed in housing 12 e to cause actuation of lancet device 10 e asdescribed in detail herein. Slide plate 164 forms the structure forcompressing drive spring 92 e alluded to previously. Rear ledge or rim162 is also adapted to engage forward rim 42 e of main body 20 e ofhousing 12 e to prevent shield body 50 e from axially sliding completelyout of housing 12 e through front opening 30 e defined in the forwardend wall 58 e of shield body 50 e. Rear rim 162 is sized such that itmay slide along the inner surface of main body 20 b when shield body 50e is retracted (i.e., depressed) into main body 20 e, as will occur whenthe lancet device 10 b is actuated by a user.

Slide plate 164 forms the internal structure in main body 20 e ofhousing 12 e which is used to cause compression of drive spring 92 ethereby storing potential energy in drive spring 92 e which, uponrelease, is used to bias lancet 70 e to the puncturing position. Slideplate 164 is disposed in main body 20 e of housing 12 e to be in contactwith rear rim 162 of shield body 50 e. Slide plate 164 is associatedwith rear rim 162 of shield body 50 e so that slide plate 164 may moverearward with shield body 50 e as shield body 50 e is retracted (i.e.,depressed) into main body 20 e of housing 12 e to arm and actuate lancetdevice 10 e. Slide plate 164 defines a generally centrally-locatedkeyhole or key opening 166 that is sized and shaped to generally conformto the transverse cross-sectional shape of carrier body 76 e of lancet70 e, to allow the cross-section of carrier body 76 e to passtherethrough during actuation of lancet device 10 e. In particular,keyhole 166 comprises a central, typically circular-shaped portion 168and two contiguous laterally-extending notches 170, which define a shapethat permits the transverse cross-section of carrier body 76 e to passtherethrough during actuation of lancet device 10 e, as discussedfurther herein.

A further difference in lancet device 10 e when compared to lancetdevices 10 a-c discussed previously lies in the formation of rear cap 24e, and the interaction therewith by slide plate 164 and shield body 50 eto cause arming and actuation of lancet device 10 e. As in previousembodiments, rear cap 24 e comprises an annular rim 36 e that engages anannular rear rim 32 e of main body 20 e of housing 12 e. In particular,annular lip 38 e on annular rim 36 e engages annular groove 34 e definedin annular rim 32 e to join rear cap 24 e to main body 20 e. However, inlancet device 10 e, annular rim 36 e is elongated and extends distally agreater distance into main body 20 e of housing 12 e, so as to bepositioned proximate to the rear rim 162 of shield body 50 e in theinitial state of lancet device 10 e. Annular rim 36 e defines a taperedinternal cam surface 172, which is shaped to impart a specific cammotion to slide plate 164 due to contact therewith and ultimately causearming and actuation of lancet device 10 e as described hereinafter.

In the initial state of lancet device 10 e, drive spring 92 e isassociated with lancet 70 e, with the drive spring 92 e extending fromthe inner side of rear cap 24 e to carrier body 76 e. In lancet device10 e, carrier body 76 e is further formed with a proximal or rear rim174 at the rearward end thereof. Rim 174 generally defines the forwardend of proximal spring guide 86 e and typically has a diameter largerthan the diameter of distal spring guide 88 e and typically at leastequal to the diameter of the forward end of drive spring 92 e. Rim 174defines a contact structure or surface on carrier body 76 e that is usedto compress drive spring 92 e to place the lancet device 10 e into aloaded or armed state. Once the drive spring 92 e is released, therebyreleasing the potential energy stored therein during the compression ofdrive spring 92 e, the drive spring 92 e will act against rear rim 174to bias lancet 70 e to the puncturing position. Guide tabs 78 e aretypically formed integrally with rear rim 174 and extend laterallytherefrom.

With the various distinguishing components of lancet device 10 e now setforth, use and operation of lancet device 10 e will now be describedwith continued reference to FIGS. 24-30. Prior to use, cover 100 eextending distally from carrier body 76 e is removed by breaking thefrangible connection with carrier body 76 e, and withdrawing cover 100 efrom forward opening 60 e in forward end wall 58 e of shield body 50 ein the manner described previously. The forward end wall 58 e of shieldbody 50 e may then be placed in contact with a target location on apatient's body. In the initial, unarmed state of lancet device 10 e, thedrive spring 92 e is substantially uncompressed (i.e., unloaded) andextends from rear rim 174 on carrier body 76 e to rear cap 24 e. In theinitial, unarmed state of lancet device 10 e, drive spring 92 e is in arelaxed condition and acts on rear rim 174 on carrier body 76 e toposition lancet 70 e at a generally fixed and stationary position withinmain body 20 e of housing 12 e, wherein the lancet 70 e occupies asubstantially fixed position relative to main body 20 e and shield body50 e. Additionally, the drive spring 92 e acting on rear rim 174 causesthe carrier body 76 e to engage (i.e., contact) the rear side of slideplate 164. In particular, drive spring 92 e in its relaxed or unloadedinitial state, causes the front side or surface of rear rim 174 andfront surface 82 e of guide tabs 78 e to be in substantial contact withthe rear side or surface of slide plate 164. Moreover, in the initialstate of lancet device 10 e, slide plate 164 is positioned in contactwith the rear rim 162 of shield body 50 e so that rear rim 174 and guidetabs 78 e of carrier body 76 e are offset vertically from the keyhole166 defined in slide plate 164. Accordingly, in the initial state oflancet device 10 e, rear rim 174 and guide tabs 78 e are in interferenceengagement with the rear side of slide plate 164.

To use the lancet device 10 e, the user grasps opposing sides of housing12 e and exerts downwardly directed force on main body 20 e thereof inthe direction of Arrow X. This force causes an opposing force on forwardend wall 58 e of shield body 50 e, causing shield body 50 e to retract(i.e., depress) axially within main body 20 e. As shield body 50 eretracts into main body 20 e, rearward end 54 e of shield body 50 emoves proximally (i.e., rearward) toward rear cap 24 e. In particular,rear rim 162 at the rearward end 54 e of shield body 50 e moves rearwardwhile simultaneously interacting with cam surface 172. Further, as rearrim 162 of shield body 50 e moves rearwardly in main body 20 e, slideplate 164 also begins to move rearwardly in combination with the rearrim 162 toward rear cap 24 e, due to the engagement between slide plate164 and rear rim 162. Additionally, lancet 70 e will move rearward withshield body 50 e and slide plate 164 due to the offset interferenceengagement between rear rim 174 and guide tabs 78 e and slide plate 164.The rearward movement of lancet 70 e will further begin to compressdrive spring 92 e, due to the engagement of drive spring 92 e with therear side of rear rim 174 on carrier body 76 e.

The downward movement imparted to housing 12 e also causes the slideplate 164 to interact with tapered cam surface 172 defined by annularrim 36 e of rear cap 24 e. Due to the tapered shape of cam surface 172from the forward or distal end of annular rim 36 e toward the CentralAxis A of lancet device 10 e, slide plate 164 moves downward in internalcavity 28 e of main body 20 e as the slide plate 164 is retracted inmain body 20 e. Accordingly, as shield body 50 e is retracted (i.e.,depressed) into main body 20 e of housing 12 e, slide plate 164 movesrearwardly and downward in main body 20 e, and this combined movementoccurs substantially simultaneously. Additionally, continued rearwardmovement of shield body 50 e has the effect of compressing the drivespring 92 e and storing the potential energy necessary to bias thelancet 70 e to the puncturing position.

Once the slide plate 164 moves downward to a position where thetransverse cross-sectional shape of the carrier body 76 e defined at thelocation of rear rim 174 and guide tabs 78 e on carrier body 76 ematches the corresponding profile of keyhole 166, the interferingengagement restraining the drive spring 92 e is removed and thepotential energy stored in drive spring 92 e is released. With thestored potential in drive spring 92 e released and providing a biasingforce acting on lancet 70 e, the drive spring 92 e biases the lancet 70e away from rear cap 24 b and through shield body 50 e. During suchpropelling movement, the corresponding guide tabs 78 e and guidechannels 80 b guide lancet 70 b axially through shield body 50 e. Thebiasing force acting on lancet 70 e is preferably sufficient to causethe puncturing end 74 e of lancet 72 e to project a sufficient distanceand with sufficient force from the forward opening 60 e in shield body50 e to cause a puncture wound at the target location on the patient'sbody. Moreover, during the propelling movement of lancet 70 e, proximalspring guide 86 e on carrier body 76 e releases from drive spring 92 ewhich remains connected to rear cap 24 e.

As the lancet 70 e moves forward in the propelling movement, distalspring guide 88 e engages retraction spring 94 e. The biasing/propellingforce provided by drive spring 92 e is at least in part applied toretraction spring 94 e by engagement of distal spring guide 88 e withretraction spring 94 e, which causes the retraction spring 94 e tocompress toward distal end pocket 98 e. The retraction spring 94 epermits puncturing end 74 e of lancet 72 e to extend through forwardopening 60 e in shield body 50 e a sufficient distance and withsufficient force to puncture the skin of the patient and initiate bloodflow, and thereafter returns lancet 70 e to a substantially fixed andstationary position within shield 14 e. Distal spring guide 88 eprovides an abutment surface for engaging internal sleeve 96 e in shieldbody 50 e supporting retraction spring 94 e to prevent lancet 70 e fromaxial movement entirely out of shield body 50 e through forward opening60 e. As the retraction spring 94 e returns to a relaxed or unloadedstate within shield body 50 e, the lancet 70 e is retracted in shield 14e and returned to a substantially fixed and stationary positioned withinshield body 14 e. Thereafter, the engagement of retraction spring 94 ewith distal spring guide 88 e maintains the lancet 70 e at a generallyfixed position within shield body 50 e. This engagement furthermaintains puncturing end 74 e shielded within shield body 50 e, andprevents further movement of lancet 70 e to the puncturing position.

Referring to FIGS. 31-37, a sixth embodiment of a lancet device 10 f isgenerally illustrated, and generally comprises a housing 12 f and alancet 70 f disposed in housing 12 f. Lancet device 10 f is similar instructure to lancet device 10 d discussed previously but includes aplate for actuating the device in a similar manner to lancet device 10 ediscussed immediately above. As with lancet device 10 d, lancet device10 f is not actuated through the retraction (i.e., depression) of ashield element into housing 12 f, and is initially provided in an armedor loaded state, with lancet 70 f ready to be biased to the puncturingposition by drive spring 92 f upon release of an interfering structure.The interfering structure in lancet device 10 f is a plate similar thatdescribed previously and additional details of which specific to thepresent embodiment will be provided herein.

In the initial, armed state of lancet device 10 f, drive spring 92 f isin a compressed (i.e., loaded) state, ready to bias the lancet 70 fthrough a puncturing procedure upon release. As the configuration of thehousing 12 f, lancet 70 f, and drive spring 92 f are generally similarto lancet device 10 d discussed previously, the following discussionwill build upon the previously discussed structure of lancet device 10d.

Housing 12 f of lancet device 10 f comprises an elongated main body 20 fthat generally defines a cylindrical and hollow configuration. The mainbody 20 f has a distal or forward end portion 22 f, and a rear cap 24 fforming a proximal or rearward end portion 26 f of the main body 20 f.The interior of housing 12 f is generally open and comprises an internalcavity 28 f. The internal cavity 28 f is closed at the rearward end dueto rear cap 24 f, and includes a front opening 30 f defined in forwardend portion 22 f of main body 20 f, and through which lancet 70 fextends when lancet device 10 f is actuated. Main body 20 f and rear cap24 f may be integrally formed. Typically, main body 20 f and rear cap 24f are separate elements that are affixed together to form housing 12 f,in the manner described previously, but may also be integral also in themanner described.

In lancet device 10 f, distal or forward end portion 22 f of main body20 d comprises an axially rearward-extending internal sleeve 96 f whichdefines a distal end pocket 98 f for receiving and supporting retractionspring 94 f. Forward rim 42 f at the forward end portion 22 f of mainbody 20 f is adapted to be placed in contact with a patient's bodyduring use of lancet device 10 f. Additionally, main body 20 f comprisesan actuation structure or actuator 180 for causing actuation of lancet70 f and corresponding release of compressed drive spring 92 f. Actuator180 generally comprises an actuating button or lever 182 that ispivotally associated with main body 20 f. The pivotal association withmain body 20 f may be in the form of a living hinge 183 or equivalentstructure and lever 182 may thus be integrally formed with main body 20f. Actuator 180 further comprises a plate member 184, which depends froman inner side of actuating lever 182 and extends downward into internalcavity 28 f of main body 20 f of housing 12 f. Plate member 184 isoriented substantially transverse to the Central Axis A of main body 20f in the initial state of actuating lever 182. Plate member 184 may beformed integrally with lever 182 or be provided as a separate componentfrom lever 182 and be joined thereto. For example, lever 182 may definea recess 186 that accepts a tab 188 extending from plate member 184 toconnect plate member 184 to lever 182. Tab 188 may be secured in recess186 via friction fit and/or with an adhesive. The pivotal connection belever 182 and main body 20 f is provided so that plate member 184 mayinteract with lancet 70 f and, further, drive spring 92 f to release thecompressed drive spring 92 f and cause actuation of lancet device 10 f.

Main body 20 f of housing 12 f comprises opposing inner sidewalls 190each defining an internal guide channel 192 for guiding movement oflancet 70 f within main body 20 f. Guide channels 192 may be formed aslongitudinally extending grooves or recesses in the inner sidewalls 190,or may be formed as part of a raised structure extending inward fromsidewalls 190. The guide channels 192 are adapted to receive to receiveguide tabs 78 f on carrier body 76 f to guide movement of lancet 70 fwithin main body 20 f. Guide channels 190 each define an end surface orstop 194, which may be use to provide a stop for guide tabs 78 f toprevent lancet 70 f from axial movement entirely out of main body 20 fthrough front opening 30 f after the lancet device 10 f is actuated.However, desirably distal spring guide 88 f may be formed to provide anabutment surface for engaging internal sleeve 96 f in shield body 50 fsupporting retraction spring 94 f to prevent lancet 70 f from axialmovement entirely out of shield body 50 f through forward opening 60 f.

Lancet 70 f is formed in a generally analogous manner to lancet 70 d oflancet device 10 d discussed previously, with carrier body 76 fincluding two outward extending guides tabs 76 f and supporting a lancet72 f with a puncturing end 74 f at the forward end thereof. As inprevious embodiments, guide tabs 78 f extending laterally outward fromcarrier body 76 f engage guide channels 190 in main body 20 f. Carrierbody 76 f further comprises a proximal or rear rim 196 at the rearwardend thereof. Rim 196 generally defines the forward end of proximalspring guide 86 f and typically has a diameter larger than the diameterof distal spring guide 88 f on carrier body 76 f, and typically at leastequal to the diameter of the forward end of drive spring 92 f. Rim 196is provided as a contact structure or surface on lancet 70 f forinterference engagement with plate member 184 to prevent actuation oflancet device 10 f, and maintain compression of drive spring 92 f in theinitial, pre-actuated state of lancet device 10 f. As indicated, thediameter of rim 196 is also typically sized to be at least equal to thediameter of drive spring 92 f and provides a contact structure orsurface that maintains drive spring 92 f in a compressed state in theinitial, pre-actuated state of lancet device 10 f. During actuation oflancet device 10 f, drive spring 92 f will act against rim 196 to biaslancet 70 f to the puncturing position, as described further herein. Ingeneral, lancet 70 f is adapted for axial movement through the internalcavity 28 f of main body 20 f between an initial position wherein platemember 184 is in interference engagement with the lancet 70 f, therebyholding or maintaining drive spring 92 f in a compressed or loadedstate, to a puncturing position where the puncturing end 74 f of lancet72 f extends beyond the front opening 30 f in main body 20 f asufficient amount to cause a puncture wound on a patient's body.

Plate member 184 defines a generally centrally-located keyhole or keyopening 197 that is sized and shaped to match the transversecross-sectional shape or outline of carrier body 76 f of lancet 70 f toallow the carrier body 76 f to pass therethrough during actuation oflancet device 10 f. In particular, keyhole 197 comprises a central,typically circular-shaped portion 198 and two contiguous laterallyextending notches 200 which define a shape that permits the carrier body76 f to pass therethrough during actuation of lancet device 10 f.

With the general components of lancet device 10 f now set forth, use andoperation of lancet device 10 f will now be described with continuedreference to FIGS. 31-37. Prior to use, cover 100 f extending distallyfrom carrier body 76 f is removed by breaking the frangible connectionwith carrier body 76 f, and withdrawing cover 100 f from the frontopening 30 f in main body 20 f in the manner described previously. Inthe initial, pre-actuated state of lancet device 10 f, plate member 184is positioned relative to carrier body 76 f such that the rear rim 196and guide tabs 78 f on carrier body 76 f are offset from keyhole 197and, therefore, in interference engagement with the rear side of platemember 184. In particular, the transverse cross-sectional shape definedby the carrier body 76 f at the location of rear rim 196 and guide tabs78 f is offset, typically vertically offset, from keyhole 197. As aresult, drive spring 92 f is held in a compressed, loaded state betweenrear rim 196 on carrier body 76 f and rear cap 24 f. The rearward orproximal end of drive spring 92 f may be secured to rear cap 24 f in themanner discussed previously in this disclosure. The forward or distalend of drive spring 92 f may be associated with the proximal springguide 86 f and rear rim 196 of carrier body 76 f in the manner describedpreviously, and may be secured to rear rim 196 by suitable means such asby adhesive and/or direct mechanical attachment.

To carry out a puncturing procedure, the user grasps opposing sides ofhousing 12 f and places the forward rim 42 f of main body 20 f incontact with a target location on a patient's body. The user then exertsdownward pressure in the direction of Arrow X on lever 182, causinglever 182 to pivot (i.e., depress) into internal cavity 28 f of mainbody 20 f. As lever 182 pivots downward in internal cavity 28 f, platemember 184 also moves downward in internal cavity 28 f while initiallymaintaining an interference engagement with lancet 70 f and therebycontinuing to maintain the drive spring 92 f in a compressed state. Inparticular, plate member 184 initially maintains an interferenceengagement with lancet 70 f, wherein the forward side or surface of rearrim 196 and forward side or surface of guide tabs 78 f on carrier body76 f are in interference engagement with the rearward side or surface ofplate member 184 thereby maintaining the drive spring 92 f compressedbetween rear rim 196 and rear cap 24 a. As the lever 182 is continued tobe depressed into main body 20 a, keyhole 197 in plate member 184eventually aligns with a matching transverse cross-sectional shapedefined by carrier body 76 f at the location of the rear rim 196 andguide tabs 78 f, thereby permitting the carrier body 76 f to passthrough keyhole 197. As the interference engagement between the rear rim196 and guide tabs 78 f and plate member 184 is released, the storedpotential energy in drive spring 92 e is also released and used to movethe lancet 70 f to the puncturing position.

As shown in FIGS. 35-37, the pivotal movement of lever 182 results in acorresponding pivotal movement by plate member 184. As a result, asplate member 184 is pivoted downward into main body 20 f, the platemember 184 begins to define an angle α with an axis perpendicular PA tothe Central Axis A of lancet device 10 f and housing 12 f in particular.As the lever 182 is further depressed into main body 20 f, the angleformed by plate member increases to angle α′. The angular orientation ofplate member 184 causes keyhole 197 to be at a slight angularorientation relative to Central Axis A. As a result, as plate member 184moves downward and slightly forward in main body 20 f, keyhole 197 doesnot align exactly along Axis PA but at an angle to this axis. Due to theangular “offset” between keyhole 197 and the Central Axis A of main body20 f, the matching transverse cross-sectional shape defined by carrierbody 76 f at the location of the rear rim 196 and guide tabs 78 f willnot pass easily through keyhole 197 unless the size of keyhole 197 isincreased to compensate for the angular orientation of plate member 184.Therefore, in lancet device 10 f it is desirable to increase the size ofkeyhole 197 to compensate for the forward angular movement of platemember 184. Alternatively, plate member 184 could be positioned in atrack such that pivotal movement of lever 182 translates into linearlytracked movement of plate member 184. Plate member 184 would still allowfor providing clearance for rear rim 196 and guide tabs 78 f to passthrough keyhole 197.

With the stored potential in drive spring 92 f released and providing abiasing force acting on lancet 70 f, the drive spring 92 f biases thelancet 70 f away from rear cap 24 f and through main body 20 f. Duringsuch propelling movement, the engagement of guide tabs 78 f in guidechannels 192 guides lancet 70 f axially through main body 20 f. Thebiasing force applied to lancet 70 f is preferably sufficient to causethe puncturing end 74 f of lancet 72 f to project a sufficient distanceand with sufficient force from the front opening 30 f in main body 20 fto cause a puncture wound in the desired location on the patient's body.Moreover, during the propelling movement of lancet 70 f, proximal springguide 86 f on carrier body 76 f releases from drive spring 92 f whichremains connected to rear cap 24 f. As the lancet 70 f moves forward inthe propelling movement, distal spring guide 88 f engages retractionspring 94 f. The biasing/propelling force of drive spring 92 f is atleast in part applied to retraction spring 94 f by engagement of distalspring guide 88 f with retraction spring 94 f, which causes theretraction spring 94 f to compress toward distal end pocket 98 f. Theretraction spring 94 f is adapted to permit puncturing end 74 f oflancet 72 f to extend through front opening 30 f in main body 20 f asufficient distance and with sufficient force to puncture the skin ofthe patient and initiate blood flow, and thereafter return lancet 70 fto a substantially fixed and stationary position within housing 12 f. Asindicated, distal spring guide 88 f desirably provides an abutmentsurface for engaging internal sleeve 96 f supporting retraction spring94 f to prevent lancet 70 f from axial movement entirely out of mainbody 20 f of housing 12 f through front opening 30 f. As the retractionspring 94 f returns to a relaxed or unloaded state within main body 20f, the lancet 70 f is retracted in main body 20 f and returned to asubstantially fixed and stationary positioned within main body 20 f.Thereafter, the engagement of retraction spring 94 f with distal springguide 88 f maintains the lancet 70 f within main body 20 f, with thepuncturing end 74 f of lancet 72 f shielded within housing 12 f andpreventing further movement of lancet 70 f to the puncturing position.

Referring to FIGS. 38-43, a seventh embodiment of a lancet device 10 gis shown and which is a variation of lancet device 10 f describedimmediately previously. Lancet device 10 g is similar in all respects tolancet device 10 f described immediately above, except for comprising adifferent configuration of actuation structure or actuator 180 g, whichwill now be detailed. Actuator 180 g of lancet device 10 g replaces thepivoting lever 182 of actuator 180 of lancet device 10 f with adepressible button 182 g, which allows plate member 184 g to bedepressed into main body 20 g directly along Axis PA, such that platemember 184 g no longer pivots into main body 20 g and thereby form anangle with Axis PA, as was the case with the lever 182 and dependingplate member 184 of actuator 180 in lancet device 10 f. Other than theforegoing difference between actuator 180 g of lancet device 10 g andactuator 180 of lancet device 10 f, all other aspects of lancet device10 g are identical to lancet device 10 f described previously.

As further shown in the FIGS. 31-43 associated with lancet devices 10 f,10 g, actuation structures or actuators 180, 180 g of these devicescomprise a structure for engaging main bodies 20 f, 20 g of housing 12f, 12 g such that, once actuation structures or actuators 180, 180 g aredepressed, the actuators 180, 180 g are prevented from returning totheir initial positions. In actuators 180, 180 g, one or more detents202, 202 g are provided on a proximal or rearward end of lever 182 and aproximal or rearward end of button 182 g, respectively. Detents 202, 202g are adapted to engage in a snap-fit or friction-fit manner with amating recess 204 defined in main bodies 20 f, 20 g. Recesses 204, 204 gin main bodies 20 f, 20 g are provided opposite to the proximal orrearward end of lever 182 and the proximal or rearward side of button182 g, respectively. In operation, as lever 182 and button 182 g aredepressed into main bodies 20 f, 20 g, respectively, detents 202, 202 gsuccessively engage the mating recesses 204, 204 g in main bodies 20 f,20 g. The mating engagement of detents 202, 202 g in mating recesses204, 204 g prevents lever 182 and button 182 g from returning to theirinitial positions. The use of multiple detents 202, 202 g allows lever182 and button 182 g to be moved in discrete downward steps or stages tothe actuating position, where keyholes 196, 196 g defined in platemembers 184, 184 g align with the matching or corresponding transversecross-sectional shape of carrier bodies 76 f, 76 g to permit lancets 70f, 70 g to move to the puncturing position.

Referring to FIGS. 44-52, an eighth embodiment of a lancet device 10 his generally illustrated, and generally comprises a housing 12 h and alancet 70 h disposed in housing 12 h. Lancet device 10 h differs fromlancet devices 10 a-c, e discussed previously, as lancet device 10 h isnot actuated through the retraction (i.e., depression) of a shieldelement into housing 12 h. However, lancet device 10 h is similar tolancet devices 10 d, 10 f, and 10 g discussed previously because lancetdevice 10 h is initially provided in an armed or loaded state, withlancet 70 h ready to be biased to the puncturing position by drivespring 92 h upon release or removal of an interfering engagement orstructure, and likewise comprises a depressible actuation structure oractuator for releasing or removing the interference engagement.Additionally, lancet device 10 h incorporates a cutting and shearingconcept such as that utilized in lancet devices 10 a, 10 b to remove theinterference engagement. As in previous embodiments, in the initialarmed state of lancet device 10 h, drive spring 92 h is in a compressed(i.e., loaded) state, ready to bias the lancet 70 h to a puncturingposition in skin-puncturing operation upon removal of an interferenceengagement.

Housing 12 h of lancet device 10 h comprises an elongated main body 20 hthat generally has a cylindrical and hollow configuration. The main body20 h has a distal or forward end portion 22 h, and a rear cap 24 hforming a proximal or rearward end portion 26 h of the main body 20 h.The interior of main body 20 h is generally open and defines an internalcavity 28 h. The internal cavity 28 h is closed at the rearward end dueto the presence of rear cap 24 h and includes a front opening 30 hdefined in forward end portion 22 h of main body 20 h, and through whichlancet 70 h extends when lancet device 10 h is actuated. Main body 20 hand rear cap 24 h may be integrally formed. Typically, main body 20 hand rear cap 24 h are separate elements that are affixed together toform housing 12 h, as illustrated, which facilitates assembly of lancetdevice 10 h. As examples, main body 20 h and rear cap 24 h may beaffixed together through an appropriate medical grade adhesive, and/ormay connected using inter-engaging structures providing a mechanicalengagement therebetween, such as a friction-fit or a snap-fitconstruction. For example, main body 20 h may comprise an annular rim 32h that cooperates with an annular rim 36 h on rear cap 24 h and which isrecessed to accept annular rim 32 h. An adhesive, such as a medicalgrade adhesive, may be used to secure annular rim 32 h with annular rim36 h. As with lancet devices 10 d, 10 f, and 10 g, distal or forward endportion 22 h of main body 20 h comprises an axially rearward-extendingsleeve 96 h which defines a distal end pocket 98 h for receiving andsupporting retraction spring 94 h.

Additionally, main body 20 h of housing 12 h further comprises apivoting actuation structure or actuator 206 in a generally analogousmanner to lancet device 10 d described previously, for causing actuationof lancet 70 h and corresponding release of drive spring 92 h. Actuationstructure or actuator 206 generally comprises an actuating lever 208that is pivotally movable relative to main body 20 h, and is desirablylocated at the rear end portion 26 h of main body 20 h proximate to rearcap 24 h. Actuating lever 208 may extend distally or forward from rearcap 24 h and be connected to rear cap 24 h by a living hinge orequivalent structure. Lever 208 may thus be integrally formed with rearcap 24 h. The lever 208 may alternatively be associated with main body20 h. For example, lever 208 may be formed as part of the rear endportion 26 h of main body 20 h, or even formed as part of the forwardend portion 22 h of main body 20 h and extend rearward or proximallytoward rear cap 24 h. In contrast to previous embodiments, lever 208comprises two opposed and depending sidewalls 210. Sidewalls 210terminate with a cutting edge or blade 212. Cutting edge 212 may be anintegral, sharp edge on sidewalls 210 or be provided as a separatecutting blade secured to the ends of sidewalls 210. Lever 208 isgenerally adapted to be depressed into the internal cavity 28 h of mainbody 20 h so that cutting edges 212 may cut or sever an interferingengagement within in main body 20 h restraining drive spring 92 h, andthereby cause actuation of lancet device 10 h as described in detailherein.

Main body 20 h of housing 12 h may be formed with a generallyrectangular cross-section as illustrated in FIG. 46 and compriseopposing inner sidewalls 213 each defining an internal shelf or ledge214. Lancet 70 h is generally adapted to engage shelves 214 forrestraining compressed drive spring 92 h and, upon depression of lever208 into main body 20 h, a structure on lancet 70 h is cut or severed torelease the interference engagement of lancet 70 h with shelves 214 and,thus, release the biasing force of drive spring 92 h. Main body 20 hdefines a main guide channel 216 that accommodates lancet 70 h andguides movement of lancet 70 h within main body 20 h.

Lancet 70 h is formed in a generally analogous manner as previousembodiments and comprises a lancet 72 h with a puncturing end 74 h atthe forward end thereof, and a carrier body 76 h supporting lancet 72 hat the rearward end thereof. The carrier body 76 h now comprises a pairof outward extending tab members 218 which generally take the place ofthe guide tabs discussed previously in this disclosure. Tab members 218are adapted for interference engagement with shelves 214 for positioninglancet 70 h in housing 12 h and main body 20 h in particular. Theinterference engagement between tab members 218 and shelves 216 furtherserves to restrain compressed drive spring 92 h. Tab members 218 areadapted to be cut or severed by cutting edge 212 on sidewalls 210 upondepression of lever 208 into main body 20 h. For this purpose, tabmembers 218 may define a tapered cross-section forming a narrow neck orweakened area 220 which may be cut through by cutting edge 212 onsidewalls 210. Neck area 220 may take other forms, such as a score line,but is generally adapted to be easily cut or sheared through (i.e.,cause failure of) by cutting edge 212 when lever 208 is depressed intomain body 20 h of housing 12 h. Carrier body 76 h further comprises aproximal or rearward end spring guide 86 h and a distal or forward endspring guide 88 h for engaging drive spring 92 h and retraction spring96 h, respectively, of lancet device 10 h. Spring guides 86 h, 88 h maybe formed integral with the body of carrier body 76 h or be provided asdistinct, separate elements and secured to the body of carrier body 76 hin the manner described previously.

In operation, lancet 70 h is adapted for axial movement through the mainguide channel 216 of main body 20 h between an initial position whereintab members 218 are in interference engagement with shelves 214 definedby main body 20 h and the puncturing end 74 h of lancet 72 h is disposedentirely within main body 20 d, to a puncturing position wherein carrierbody 76 h is disposed in main guide channel 216 with the puncturing end74 h extending beyond front opening 30 h of main body 20 h a sufficientdistance to cause a puncture wound in a patient's body. In the initial,pre-actuated state of lancet device 10 h, drive spring 92 h is at leastpartially compressed between rear cap 24 h and carrier body 76 h andtypically has sufficient stored potential energy to conduct askin-piercing procedure. The rearward or proximal end of drive spring 92h is typically secured to rear cap 24 h in the manner discussedpreviously in this disclosure. The forward or distal end of drive spring92 h is associated with carrier body 76 h and disposed about proximalspring guide 86 h, and may be secured to carrier body 76 h by similarmeans discussed previously, as by suitable adhesive or direct mechanicalattachment. As shown, for example, in FIG. 47, drive spring 92 hdirectly engages carrier body 76 h, and the carrier body 76 h mayfurther comprise two outward-extending tabs or flanges 222 against whichthe forward end of drive spring 92 h is engaged to provide additionalsurfaces for transmitting the biasing force of drive spring 92 h tolancet 70 h to move the lancet 70 h to the puncturing position.

With continued reference to FIGS. 44-52, use and operation of lancetdevice 10 h will now be discussed. As with previous embodiments, a cover(not shown) extending distally from carrier body 76 h may be providedwith carrier body 76 h. As with previous embodiments, such a cover wouldbe removed by breaking the frangible connection with carrier body 76 hand withdrawing the cover from front opening 30 h in main body 20 h.Forward end rim 42 h of main body 20 h may then be placed in contactwith the target location on the patient's body. As indicated previously,lancet device 10 h is initially provided in an armed state, with lancet70 h ready to initiate a puncturing procedure when compressed drivespring 92 h is released.

To carry out a puncturing procedure, the user grasps opposing sides ofhousing 12 h and exerts downwardly directed force in the direction ofArrow X on lever 208, causing lever 208 to pivot (i.e., depress) intointernal cavity 28 h of main body 20 h. As lever 208 is depressed intomain body 20 h, depending sidewalls 210 and, more particularly, cuttingedge 212 at the end of each depending sidewall 210 contacts tab members218 at the reduced cross-sectional, weakened area 220 on tab members218. As the lever 208 is continued to be depressed into main body 20 h,cutting edge 212 on sidewalls 210 begins to cut through the neck area220 on each tab member 218. Once the tab members 218 are completelycut-through, the interference engagement between tab members 218 andshelves 214 defined by sidewalls 213 of main body 20 h is removed,releasing the drive spring 92 b to bias lancet 70 h to the puncturingposition. With the biasing force of drive spring 92 h released, drivespring 92 h thereafter biases the lancet 70 h away from rear cap 24 hand through main guide channel 216. The biasing force imparted to lancet70 h is preferably sufficient to cause the puncturing end 74 h of lancet72 h to project a sufficient distance and with sufficient force from thefront opening 30 h in main body 20 h to cause a puncture wound in thedesired location on the patient's body. Moreover, during the propellingmovement of lancet 70 h, proximal spring guide 86 h on carrier body 76 hreleases from drive spring 92 h which remains connected to rear cap 24h.

As the lancet 70 h moves forward in the propelling movement, distalspring guide 88 h engages retraction spring 94 h. The biasing/propellingforce provided by drive spring 92 h is at least in part applied toretraction spring 94 h by engagement of distal spring guide 88 h withretraction spring 94 h, which causes the retraction spring 94 h tocompress toward distal end pocket 98 h. The retraction spring 94 hpermits puncturing end 74 h of lancet 72 h to extend through frontopening 30 h in main body 20 h a sufficient distance and with sufficientforce to puncture the skin of the patient and initiate blood flow, andthereafter return lancet 70 h to a substantially fixed and stationaryposition within housing 12 h. Carrier body 76 h is desirably formed witha shoulder 224 formed at the base of distal spring guide 88 h, and whichis configured to engage an abutment surface or stop 226 defined bysidewalls 213 of main body 20 h in main guide channel 216 to preventlancet 70 h from axial movement entirely out of main body 20 h throughfront opening 30 h. The stop 226 is defined rearward ofrearward-extending internal sleeve 96 h supporting retraction spring 94h. As the retraction spring 94 h returns to a relaxed or unloaded statewithin main body 20 h, the lancet 70 h is retracted in main body 20 hand returned to a substantially fixed and stationary positioned withinmain body 20 h. Thereafter, the engagement of retraction spring 94 hwith distal spring guide 88 h maintains the lancet 70 h shielded withinhousing 12 h, and prevents further movement of lancet 70 h to thepuncturing position, in the manner discussed in detail previously. Inthis disclosure, various elements have been identified as being adaptedto be “cut”, “sheared”, “yielded”, “fractured” to cause release andactuation of lancet device 10. These terms may all be grouped under acommon heading of a “failure” item or element which is intended to failwhen force is applied thereto in whatever form, for example blunt forceor a cutting force.

Referring to FIGS. 53-55, a modification to a lancet device disclosed inU.S. patent application Ser. No. 11/270,330, filed Nov. 30, 2004, andentitled “Contact Activated Lancet Device”, the entire disclosure ofwhich is incorporated herein by reference, is shown. Lancet device 10disclosed in the foregoing incorporated reference document may include amodified version of a retaining hub 90 i. FIG. 53 shows the retaininghub 90 i as part of the lancet device 10 disclosed in the incorporatedreference document, the disclosure of which will be used to describe thelocation and operation of retaining hub 90 i. Retaining hub 90 igenerally defines an annular shape and is adapted to maintain the lancet70 in an initial armed position retracted within housing 12. Retaininghub 90 i typically includes two opposed and elongated support members 91i connected by two pivotal cam elements 92 i to form the annular shapeof retaining hub 90 i. Cam elements 92 i each include twooutward-extending shafts 93 i engaged pivotally with the opposed supportmembers 91 i. Cam elements 92 i each further include at least onetypically wedge-shaped contact element 94 i defining an upper contactsurface 96 i on the upper surface thereof. Cam elements 92 i eachfurther define a generally centrally located recess or cut-out 100 idefined in a bottom side thereof. The purpose of recess 100 i isdescribed herein in connection with the operation of retaining hub 90 iin lancet device 10. As shown in FIGS. 54 and 55, the cam elements 92 idesirably each include two contact elements 94 i disposed generally atopposite ends of the cam elements 92 i, with the recess 100 i defined inthe bottom side of the cam elements 92 i between the contact elements 94i.

In lancet device 10, retaining hub 90 i and lancet 70 are ininterference engagement with each other, such that retaining hub 90 iretains the lancet 70 in an initial armed state retracted within housing12. For example, fingers 82 on carrier element 76 may rest on the upperside of cam elements 92 i, thereby providing interference engagementbetween the lancet 70 and the retaining hub 90 i. Moreover, uppercontact surface 96 i on the contact elements 94 i may be adapted forcontacting engagement with structure within housing 12. For example,rear cap 24 of housing 12 may include structure extending therein, suchas internal contact 46 integrally formed and extending on at least one,and desirably on two opposing inner sidewalls thereof. As retaining hub90 i typically includes two contact elements 94 i on each cam element 92i, two internal contacts 46 may be provided on each of the two opposinginner sidewalls of the housing 12. Each internal contact 46 includes adistal engagement cam surface 47 for contacting engagement with thecorresponding contact surface 96 i on contact elements 94 i.

During usual operation of the lancet device 10, axial movement of shieldbody 50 toward rear cap 24, causes the retaining hub 90 i to bedisplaced rearwardly toward rear cap 24, with fingers 82 of the carrierelement 76 resting upon the cam elements 92 i. Such rearward movement ofretaining hub 90 i causes the contact surfaces of engagement camsurfaces 47 of the internal contacts 46 within rear cap 24 to engage andco-act with the corresponding contact surfaces 96 i on the contactelements 94 i of cam elements 92 i. Such engagement and continueddownward movement of internal contacts 46 causes the cam elements 92 ito pivot on or rotate about shafts 93 i with respect to support members91 i. Due to the generally wedge-shaped profile of the contact elements94 i, the pivotal movement of cam elements 92 i has the effect offurther compressing drive spring 102 by further “lifting” fingers 82, atleast until the point where rear nub 86 on carrier element 76 contactsthe inner side of rear cap 24. At this point, continued axialdisplacement of shield body 50 toward rear cap 24 pivots cam elements 92i to a position where recess 100 i defined in the bottom side of camelements 92 i has rotated to a position generally aligned with fingers82 at which point the interference engagement between fingers 82 and camelements 92 i is released by such alignment. The biasing force of drivespring 102 then propels lancet 70 downward away from the rear cap 24axially through housing 12 and shield body 50, with guide tabs 78passing axially through the annular opening defined by retaining hub 90i.

Referring to FIGS. 56-67, a final embodiment of a lancet device 10 k isgenerally shown. Lancet device 10 k generally includes a housing 12 k, ashield 14 k movably associated with the housing 12 k, and a lancet 70 kmovably disposed in housing 12 k. Shield 14 k is movably associated withhousing 12 k, and is at least partially disposed within housing 12 k.Shield 14 k extends outward from housing 12 k, while the lancet 70 iscontained within housing 12 k and is typically axially movable throughthe shield 14 k.

Housing 12 k comprises an elongated main body 20 k having a generallycylindrical and hollow configuration. Main body 20 k has a distal orforward end portion 22 k, and a rear cap 24 k forming a proximal orrearward end portion 26 k of the main body 20 k. The interior of mainbody 20 k is generally open and comprises an internal cavity or bore 28k. The internal cavity 28 k is closed at the rearward end due to thepresence of rear cap 24 k, and includes a front opening 30 k defined byforward end portion 22 k of main body 20 k, and through which shield 14k extends. Main body 20 k and rear cap 24 k may be integrally formed.Alternatively, main body 20 k and rear cap 24 k may be separate elementsthat are affixed together to form housing 12 k in the general mannerdescribed previously in this disclosure. Main body 20 k further includesa forward rim 42 k formed as part of forward end portion 22 k and whichdefines front opening 30 k.

Shield 14 k is typically a generally cylindrical, hollow structurecomprising a shield body 50 k having a distal or forward end 52 k and aproximal or rearward end 54 k, and defines an internal cavity or bore 56k extending therethrough. Forward end 52 k of shield body 50 k defines apartial forward end wall or rim 58 k defining a forward opening 60 k,through which a puncturing element of lancet 70 k extends when lancetdevice 10 k is actuated by a user. Forward end wall 58 k typicallydefines a small contact area about forward opening 60 k for contactingan intended puncture area on a patient's body. The reduced contact areamay be made smaller (i.e., reduced in surface area) by providing aplurality of peripheral indentations (not shown) formed perimetricallyin shield 14 k. The external surface features of housing 12 k and shield14 k may be formed in accordance with the ergonomic features andstructure disclosed in application Ser. No. 11/123,849 incorporated byreference previously in this disclosure. Rearward end 54 k of shieldbody 50 k defines a rear rim 63 k.

Shield 14 k is typically axially and slidably movable within housing 12k. Shield 14 k and housing 12 k may be coaxially associated, with shield14 k and housing 12 k coaxially disposed around a common Central Axis A.Shield 14 k and housing 12 k may each be generally cylindrical-shaped. Arotation element or cam follower, typically a guide plate 262 is furtherassociated with shield 14 k. In particular, guide plate 262 is disposedat the rearward end 54 k of shield body 50 k and engages rear rim 63 kof shield body 50 k. Plate 262 is a generally annular-shaped structureand defines a central opening 263 with two opposed clearance slots 264and two opposed guide slots 266. Clearance slots 264 and guide slots 266are orientated along axes that are generally orthogonal to one another.An outer periphery or perimeter of plate 262 is formed with two opposedcam guide recesses 268 for receiving and engaging a cam structureadapted to cause rotation of plate 262 to cause actuation of lancetdevice 10 k as described further herein. Plate 262 is typically inrotational sliding engagement or contact with rear rim 63 of shield body50 k to permit rotation thereof relative to rear rim 63. In particular,plate 262 comprises a bottom side 270 in contact with rear rim 63 k andan upper side 272 facing away from rear rim 63 k. Due to the contactbetween the bottom side 270 of plate 262 and rear rim 63, plate 262 isadapted to slide together with shield body 50 k in main body 20 k whenaxial motion is imparted to shield body 50 k, for example by axiallyretracting (i.e., depressing) shield body 50 k into main body 20 k toactuate lancet device 10 k as described herein. Accordingly, any axialmotion applied to shield body 50 k to retract (i.e., depress) shieldbody 50 k into main body 20 k of housing 12 k will be transmitted toplate 262 through the contact engagement of rear rim 63 k and plate 262.

Lancet device 10 k further comprises a lancet 70 k disposed within thehousing 12 k, and extending into shield 14 k. Lancet 70 k includes apuncturing element shown in the form of a lancet 72 k. Lancet 72 kcomprises a puncturing end 74 k at the forward end thereof. Lancet 70 kis generally adapted for axial movement through the internal cavity 56 kof shield body 50 k between an initial position, wherein the puncturingend 74 k is disposed within shield body 50 k, to a puncturing positionwherein the puncturing end 74 k extends beyond the forward opening 60 kof shield body 50 k a sufficient distance to cause a puncture wound in apatient's body. The puncturing end 74 k of lancet 72 k is adapted forpuncturing the skin of a patient, and may be in the form of a pointedend, needle tip, blade edge, and the like. Puncturing end 74 k mayinclude a preferred alignment orientation, such as with a pointed end ora blade aligned in a specific orientation. In such an orientation,shield body 50 k and/or main body 20 k of housing 12 k may includetarget indicia corresponding to the alignment orientation of puncturingend 74 k. Indentations (not shown) in the shield body 50 k and/orindentations (not shown) in main body 20 k may function as such analignment orientation, as described previously in this disclosure.

Lancet 70 k comprises a carrier body 76 k supporting lancet 72 k at therearward end thereof. Carrier body 76 k and shield body 50 k may includecorresponding guiding surfaces for guiding the movement of lancet 70 kin shield body 50 k. For example, carrier body 76 k may include guidetabs 78 k on an external surface thereof, with shield body 50 k definingcorresponding guide channels 80 k extending longitudinally along aninner wall thereof for accommodating guide tabs 78 k slidably thereinupon actuation of lancet device 10 k. Carrier body 76 k may include apair of elongated guide tabs 78 k on opposing lateral sides thereof asillustrated, or a single elongated guide tab 78 k, and shield body 50 kmay include a corresponding pair of guide channels 80 k extending alongopposing inner surfaces thereof corresponding to each of the guide tabs78 k, or a single corresponding guide channel 80 k. The engagement ofguide tabs 78 k in guide channels 80 k in the initial, pre-actuatedstate of lancet device 10 k ensures that lancet 70 k is prevented fromsubstantial rotation in shield body 50 k during the actuation sequenceof lancet device 10 k, wherein plate 262 is set into sliding rotationalmovement relative to rear rim 63 k as described herein. Upon actuation,engagement of guide tabs 78 k in guide channels 80 k guides movement oflancet 70 k to the puncturing position.

As shown in FIG. 60, in addition to two opposed guide tabs 78 k, carrierbody 76 k further comprises two actuation tabs 81 k oriented along anaxis generally orthogonal to an axis passing through guide tabs 78 k.Actuation tabs 81 k form part of the actuation structure or actuator oflancet device 10 k. Actuation tabs 81 are shorter in length than guidetabs 78 k, which typically extend approximately the length of carrierbody 76 k. Actuation tabs 81 k comprise a distal facing surface 82 kadapted to engage or rest upon the upper side 270 of guide plate 262 inthe initial, pre-actuated state of lancet 70 k. Actuation tabs 81 k aregenerally adapted to mate or align with clearance slots 264 in plate 262when plate 262 is rotated to the appropriate alignment position withactuation tabs 81 k to allow actuation of lancet device 10 k asdescribed herein. Likewise, guide tabs 78 k are sized to mate with guideslots 266 in plate 262. However, guide tabs 78 k generally extend atleast partially through guide slots 266 in the initial, pre-actuatedstate of lancet device 10 k, and the guide slots 266 are typically sizedlarger enough to allow plate 262 to rotate relative to carrier body 76 kwithout guide tabs 78 k interfering with such rotation due to theirpresence in guide slots 266.

Shield body 50 k may define additional internal guide channels 84 k forreceiving actuation tabs 81 k when the interference engagement betweenactuation tabs 81 k and plate 262 is removed by rotation of plate 262.Such additional guide channels 84 k are optional as the association ofguide tabs 78 k and guide channels 84 k is typically sufficient to guidethe movement of carrier body 76 k during the puncturing movement oflancet 70 k. If provided, additional guide channels 84 k may extend theinternal length of shield body 50 k or along only a portion of thelength of shield body 50 k. Carrier body 76 k further comprises aproximal or rearward end spring guide 86 k and a distal or forward endspring guide 88 k for engaging a drive spring and retraction spring,respectively, of lancet device 10 k as described herein. Spring guides86 k, 88 k may be formed integral with the carrier body 76 k or beprovided as distinct, separate elements in the manner describedpreviously in this disclosure.

Movement of the lancet 70 k through the lancet device 10 a is achievedthrough a biasing force provided by a drive spring 92 k. Drive spring 92k is adapted to exert a biasing force against lancet 70 k to drivelancet 70 k through lancet device 10 k toward the puncturing position,and is disposed between the rearward end of main body 20 k and thelancet 70 k. Rear cap 24 k may include structure for alignment of and/orfor maintaining drive spring 92 k in the proper orientation on rear cap24 k. For example, rear cap 24 k may include an internal alignmentstructure (not shown) for correctly positioning the drive spring 92 k.Lancet 70 k, as indicated previously, includes proximal spring guide 86k which engages the opposite end of drive spring 92 k in the initial orpre-actuated state of lancet device 10 k. Guide tabs 78 k and actuationtabs 81 k may be used as additional or replacement structure forengaging the distal end of drive spring 92 k.

In the initial state of lancet device 10 k, drive spring 92 k istypically in a generally uncompressed, unloaded state between rear cap24 k and distal spring guide 86 k of carrier body 76 k. However, drivespring 92 k may exert a limited forward biasing or positioning force oncarrier body 76 k via proximal spring guide 86 k to help maintain theinterference engagement between actuation tabs 81 k and plate 262.Alternatively, drive spring 92 k may be partially compressed betweenrear cap 24 k and carrier body 76 k and is adapted for furthercompression therebetween. During actuation of lancet device 10 k, theretraction of shield body 50 k into main body 20 k causes compression orfurther compression of drive spring 92 k due to the interferenceengagement between lancet 70 k and plate 262, thereby storing potentialenergy in drive spring 92 k necessary to bias lancet 70 k to thepuncturing position. As shield body 50 k is further retracted into mainbody 20 k, the rotation of plate 262 relative to lancet 70 k eventuallyremoves the interference engagement between actuation tabs 81 k andplate 262, thereby releasing the potential energy stored in compresseddrive spring 92 k as kinetic energy applied to lancet 70 k to biaslancet 70 k to the puncturing position.

A retraction or return spring 94 k may further be provided at theforward end of the lancet device 10 k, for retracting the lancet 70 kwithin shield body 50 k after lancet 70 k has moved axially to thepuncturing position wherein puncturing element 74 k extends outward fromthe distal or forward end 52 k of shield body 50 k. Retraction spring 94k is adapted to be engaged by distal spring guide 88 k extending forwardfrom carrier body 76 a during the forward, puncturing movement of lancet70 k, as described herein. The forward end wall 58 k of shield body 50 kforms a distal end pocket 98 k for receiving and supporting retractionspring 94 k. Retraction spring 94 k is disposed in distal end pocket 98k throughout the operation sequence of lancet device 10 a in apuncturing procedure. Retraction spring 94 k may be secured to theinternal side of the forward end wall 58 k of shield body 50 k throughuse of a medical grade adhesive or by mechanically securing retractionspring 94 k thereto in the manner described previously in thisdisclosure. Drive and retraction springs 92 k, 94 k are typicallycompression springs capable of storing potential energy when in acompressed state. Lancet device 10 k may further include a protectivetab or cover 100 k for protectively covering the forward end of thelancet 70 k as described in previous embodiments. The respectiveelements of the lancet device 10 k are all typically formed of moldedplastic material, such as a medical grade plastic material. Lancet 72 kmay be constructed of any suitable material adapted for puncturing theskin, and is typically a surgical grade metal such as stainless steel.

Rear cap 24 k of housing 12 k further comprises internal structureadapted to interact with plate 262 to cause actuation of lancet device10 k. In particular, rear cap 24 k is formed with at least one andtypically two distally-extending actuation members typically camelements 280 each having a tapered cam surface 282 formed on theirdistal ends. Cam elements 280 are formed to extend distally into therespective cam guide recesses 268 in plate 262. The cam interactionbetween cam elements 280 and plate 262 provides the means by which theinterference engagement between the lancet 70 k and plate 262 is removedto allow lancet 70 k to move to the puncturing position. Moreparticularly, the interaction between the tapered cam surfaces 282 oncam elements 280 and cam guide recesses 268 in plate 262 during theretracting movement of shield body 50 k into main body 20 k causessufficient rotational movement of plate 262 relative to carrier body 76k to allow actuation tabs 81 k to align with clearance slots 264 inplate 262 to remove the interference engagement between lancet 70 k andplate 262. As indicated previously, such rotational movement of plate262 is sliding rotational movement on rear rim 63 k of shield body 50 k.Also as indicated previously, guide slots 266 in plate 262 arepreferable sized sufficiently to allow plate 262 to rotate to thealignment position without guide tabs 78 k interfering with suchrotation.

Due to the elongated length of cam elements 280, shield body 50 kdefines opposed cut-outs or notches 284 to accommodate the distal tipsof cam elements 280 extending through cam guide recesses 268 in theinitial, pre-actuated state of lancet device 10 k, and the eventualforward position of the distal tips of cam elements 280 as shield body50 k is retracted into main body 20 k to cause actuation of lancetdevice 10 k. Cam guide recesses 268 are initially offset from notches284 but as plate 262 is rotated to the alignment position cam guiderecesses 268 eventually align with notches 284 as shown in FIG. 62. Theengagement of cam elements 280 with plate 262 in cam guide recesses 268provides an additional advantage of maintaining or locking theorientation of plate 262 on rear rim 63 k of shield body 50 k. Thus,plate 262 will be prevented or inhibited from disengaging from andfalling off of rear rim 63 k should lancet device 10 k be turned upsidedown (i.e., shield 14 k pointed upward) prior to use. Additionalstructure extending from rear cap 24 k or internally from the inner wallof main body 20 k of housing 12 k may be provided to maintain thepositioning of plate 262 on rear rim 63 k of shield body 50 k.

Additionally, in order to prevent the possibility of rotational motionimparted to plate 262 by cam elements 280 from being transmitted toshield body 50 k, shield body 50 k may comprise longitudinally-extendingouter ribs 288 which are adapted to cooperate with interfering structureon the inner wall of main body 20 k, such as an engaging tab or detent(not shown). The engagement of such a tab or detent with ribs 288 willsubstantially lock the orientation of shield body 50 k relative mainbody 20 k and prevent rotation of shield body 50 k relative to main body20 k. Moreover, engagement ribs 288 may be used as guiding structure toguide the retracting movement of shield body 50 k into main body 20 kduring actuation of lancet device 10 k. Shield body 50 k further definesan abutment shoulder 290 at forward end 52 k. Abutment shoulder 290 isadapted for interference engagement with forward rim 42 k of main body20 k to prevent shield body 50 k and, thus, lancet 70 k from axialforward movement out of main body 20 k through front opening 30 k.Additionally, the limited positioning or biasing force of drive spring92 k on lancet 70 k in the initial, pre-actuated state of lancet device10 k is transmitted by the interference engagement between plate 262 andshield body 50 k to shoulder 290, which then engages forward rim 42 k.

Use and actuation of lancet device 10 k will now be described withcontinued reference to FIGS. 56-67. Lancet device 10 k is typicallyinitially provided with cover 100 k extending distally from carrier body76 k, and through forward opening 60 k in forward end wall 58 k ofshield body 50 k. In the initial, pre-actuated state of lancet device 10k, drive spring 92 k is typically uncompressed between the inner side ofrear cap 24 a and proximal spring guide 86 a of carrier body 76 a, andlancet 70 k is initially in interference engagement with plate 262, forexample under the limited position or biasing force provided by drivespring 92 k. In particular, actuation tabs 81 k extending from carrierbody 76 k rest upon the upper side 270 of plate 262 and are offset frommating clearance slots 264 in plate 262. Further, in the initial,pre-actuated state of lancet device 10 k, guide tabs 78 k are disposedin guide channels 80 in shield body 50 k, and extend proximally throughguide slots 266 in plate 262. As indicated previously, the engagement ofguide tabs 78 k in guide channels 80 k prevents rotation of lancet 70 kin shield body 50 k and, more particularly, carrier body 76 k in shieldbody 50 k during the rotational movement of plate 262 used to releasethe interference engagement between actuation tabs 81 k and plate 262,as described herein. Cam elements 280 extending distally from rear cap24 k extend at least partially through the respective cam guide recesses268 defined in the periphery of plate 262. Typically, the tapered camsurfaces 282 of cam elements 280 contact plate 262 within cam guiderecesses 268 to allow cam elements 280 to effect the rotational movementof plate 262 when shield body 50 k is retracted (i.e., depressed) intomain body 20 k, and secondarily to maintain plate 262 associated withrear rim 63 k of shield body 50 k. As described previously, guide slots266 in plate 262 are sized to accommodate guide tabs 78 k and to allowplate 262 to rotate relative carrier body 76 k without guide tabs 78 kinterfering with such rotational movement necessary to allow actuationtabs 81 k into alignment with clearance slots 264 in plate 262. In thisinitial, pre-actuated state of lancet device 10 k, cam guide recesses268 are offset from notches 284 in shield body 50 k with the only thedistal tips of cam elements 280 extending through cam guide recesses 268as shown in FIG. 65B.

To use the lancet device 10 k, the user grasps opposing sides of housing12 k, such as between a finger and thumb, and removes breakable cover100 k. Cover 100 k is removed typically by moving cover 100 k in acombined twisting and pulling motion in forward opening 60 k in forwardend wall 58 a of shield body 50 k to break the frangible connection withcarrier body 76 k. Once the frangible connection is broken, cover 100 kmay be removed through the forward opening 60 k. Forward end wall 58 kof shield body 50 k may then be placed in contact with a location on thepatient's body where it is desired to cause a puncture injury toinitiate blood flow. If provided, target indicia may be aligned with thedesired location of puncture.

Once placed against the body, the user exerts a downwardly directedforce on main body 20 k of housing 12 k forcing shield body 50 k ofshield 14 k to retract (i.e., depress) into housing 12 k. In particular,the user applies a downward directed force in the direction of Arrow X,thereby applying a force against the user's body (i.e., skin surface).Such force establishes an opposing force on forward end wall 58 k ofshield body 50 k causing shield body 50 k to retract axially within mainbody 20 k of housing 12 k. As shield body 50 k retracts into main body20 k, rearward end 54 k of shield body 50 k moves proximally (i.e.,rearward) toward rear cap 24 k. The engagement between rear rim 63 k atthe rearward end 54 k of shield body 50 k and plate 262 causes plate 262to move together with shield body 50 k toward rear cap 24 k. As theentire lancet 70 k moves rearward due to the interference engagementbetween actuation tabs 81 k and plate 262, drive spring 92 k begins tocompress or compresses further between rear cap 24 k and carrier body 76k and, more particularly, between proximal spring guide 86 k and rearcap 24. Substantially simultaneously, cam elements 280 interact withplate 262 in cam guide recesses 268 in plate 262, and act upon plate 262to cause plate 262 to slidably rotate on rear rim 63 of shield body 50k. In particular, as shield body 50 k moves proximally, tapered camsurfaces 282 on cam elements 280 engage plate 262 in cam guide recesses268 causing plate 262 to rotate. The tapered form of tapered cam surface282 converts the linear retraction motion imparted to shield body 50 kto rotational movement of plate 262. The engagement of guide tabs 78 kin guide channels 80 k prevents lancet 70 k and carrier body 76 k inparticular from rotating in shield body 50 k. As shown in FIG. 66B, thedistal ends of cam elements 280 project further through cam guiderecesses 268 as cam elements 280 rotate plate 262 toward the releaseposition where actuation tabs 81 k align with clearance slots 264 inplate 262.

As the entire lancet 70 k continues move rearward due to theinterference engagement between actuation tabs 81 k and plate 262, drivespring 92 k continues to compress between rear cap 24 k and proximalspring guide 86 k, and am elements 280 continue to rotate plate 262 onrear rim 63 k of shield body 50 k. Eventually, plate 262 rotates to therelease position where actuation tabs 81 k align with clearance slots264 in plate 262, as shown in FIG. 67B. When this occurs, theinterference engagement between actuation tabs 81 k and plate 262 isreleased. At the moment the actuation tabs 81 k align with clearanceslots 264, the restraining force applied to drive spring 92 k due to theinterference engagement between actuation tabs 81 k and plate 262 isreleased, releasing the stored potential energy in drive spring 92 k askinetic energy used to move lancet 70 k forward in shield body 50 k.With the stored potential energy in compressed drive spring 92 kreleased as kinetic energy, drive spring 92 k biases lancet 70 k awayfrom rear cap 24 k and through internal cavity 56 k in shield body 50 k.During such movement, corresponding guide tabs 78 k and guide channels80 k guide lancet 70 k axially through shield body 50 k. The biasingforce acting on lancet 70 k is preferably sufficient to cause thepuncturing end 74 k of lancet 72 k to project a sufficient distance andwith sufficient force from the forward opening 60 k in shield body 50 kto cause a puncture wound in the desired location on a patient's body.Moreover, during the propelling axial movement of lancet 70 k, proximalspring guide 86 k on carrier body 76 k of lancet 70 k releases fromdrive spring 92 k which remains connected to rear cap 24 k. In lancetdevice 10 k, lancet 70 k is limited to axial movement only with respectto shield 14 k and housing 12 k.

Moreover, as lancet 70 k moves forward in the propelling movement,distal spring guide 88 k engages the rearward end of retraction spring94 k. The biasing force provided by drive spring 92 k is at least inpart applied to retraction spring 94 k by engagement of distal springguide 88 k with the rearward end of retraction spring 94 a which causesretraction spring 94 k to compress toward distal end pocket 98 k andstore potential energy. Retraction spring 94 k is designed such that itmay be compressed in whole or in part by the biasing force of drivespring 92 k propelling lancet 70 k, but still permits puncturing end 74k of lancet 72 k to extend through forward opening 60 k in shield body50 k a sufficient distance and with sufficient force to puncture theskin of the patient and initiate blood flow. Guide channels 84 kassociated with actuation tabs 81 k may be formed with abutment surfacesfor engagement by actuation tabs 81 k during the forward movement oflancet 70 k to prevent lancet 70 k from axial movement entirely out ofshield body 50 k through forward or front opening 60 k. Alternatively,carrier body 76 k and/or distal spring guide 88 k may be adapted forinterference engagement with forward end wall 58 of shield body 50 k toprevent lancet 70 k from axial movement entirely out of shield body 50 kthrough forward or front opening 60 k

As indicated previously, retraction spring 94 k is typically acompression spring and will have sufficient resilience to return to arelaxed, unloaded state within shield body 50 k after the lancet 70 kextends to the puncturing position. Accordingly, once the retractionspring 94 k is compressed it will provide a return biasing force on thelancet 70 k by engagement with the distal spring guide 88 k on carrierbody 76 k. Retraction spring 94 k thereby acts between the forward endwall 58 k of the shield body 50 a and distal spring guide 88 k oncarrier body 76 k to cause complete retraction of lancet 70 k intoshield body 50 k. In particular, retraction spring 94 k applies a returnbiasing force that retracts the puncturing end 74 k of lancet 72 kentirely within shield body 50 k. Moreover, as the retraction spring 94k returns to a relaxed or unloaded state within shield body 50 k, lancet70 k is returned to a static position within shield body 50 k, whereinlancet 70 k is disposed at a relatively fixed and stationary positionwithin shield body 50. Once retraction spring 94 k returns to a relaxedor uncompressed state, retraction spring 94 k maintains lancet 70 kdisposed within the shield body 50 k with puncturing end 74 k shieldedwithin shield body 50 k, and prevents further movement of lancet 70 ktoward the puncturing position.

While the invention was described with reference to several distinctembodiments of the lancet device, those skilled in the art may makemodifications and alterations to the invention without departing fromthe scope and spirit of the invention. Accordingly, the above detaileddescription is intended to be illustrative rather than restrictive. Theinvention is defined by the appended claims, and all changes to theinvention that fall within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. A lancet device, comprising: a housing; a shieldmovably associated with the housing; a lancet disposed in the housingand comprising a tip, the lancet adapted for axial movement between afirst position where the tip is disposed within the shield and a secondposition where the tip extends through a forward opening in the shield;a drive member disposed at a rearward end of the housing for biasing thelancet to the second position; and an actuator associated with thehousing and engaged with the lancet to maintain the lancet in the firstposition, wherein movement of the shield into the housing causesdisengagement of the actuator from the lancet and release of the atleast partially compressed drive member thereby enabling the drivemember to bias the lancet to the second position, wherein the actuatoris generally annular, wherein the actuator further comprises a surfacethat engages a part of the lancet to maintain the lancet in the firstposition, and wherein the surface is caused to move away from the lancetfor disengagement of the actuator.
 2. The lancet device of claim 1,wherein the surface is annularly discontinuous.
 3. The lancet device ofclaim 1, wherein axial movement of the shield into the housing causesthe drive member to expand radially outward from the lancet causingdisengagement of the actuator from the lancet.
 4. The lancet device ofclaim 1, wherein the actuator comprises a sleeve portion associated withthe housing and wherein the sleeve portion and drive member areintegrally formed.
 5. The lancet device of claim 4, wherein the housingincludes a recess in a sidewall portion configured for receiving andconstraining the sleeve portion of the actuator.
 6. The lancet device ofclaim 1, wherein the actuator comprises at least one elastic element inengagement with the lancet and axial movement of the shield into thehousing causes the at least one elastic element to contact a cammingsurface to cause the at least one elastic element to expand radiallyoutward from the lancet.